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1933 Act File No.: 333-104669

1940 Act File No.: 811-00266

U.S. SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-2

REGISTRATION STATEMENT

UNDER

and/or

REGISTRATION STATEMENT

UNDER

Exact Name of Registrant as Specified in Charter:

TRI-CONTINENTAL CORPORATION

Address of Principal Executive Offices (Number, Street, City, State, Zip Code):

225 Franklin Street, Boston, Massachusetts 02110

Registrant’s Telephone Number, including Area Code:

(800) 345-6611

Name and Address (Number, Street, City, State, Zip Code) of Agent for Service:

Scott R. Plummer, 5228 Ameriprise Financial Center, Minneapolis, MN 55474

Approximate Date of Proposed Public Offering: As soon as practicable after the effective date of this Registration Statement.

If any securities being registered on this form will be offered on a delayed or continuous basis in reliance on Rule 415 under the Securities Act of 1933, other than securities offered in connection with a dividend reinvestment plan, check the following box.  ¨

It is proposed that this filing will become effective (check appropriate box)

If appropriate, check the following box:

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PROSPECTUS

May 1, 2015

TRI-CONTINENTAL CORPORATION

Tri-Continental Corporation seeks future growth of both capital and income while providing reasonable current income.

The Securities and Exchange Commission has neither approved nor disapproved these securities, and it has not determined this Prospectus to be accurate or adequate. Any representation to the contrary is a criminal offense.

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an investment you can live with

Prospectus

May 1, 2015

225 Franklin Street

Boston, Massachusetts 02110

Toll-Free Telephone (800) 345-6611, option 3

Tri-Continental Corporation (the “Fund”) is a diversified, closed-end management investment company — a publicly traded investment fund. The Fund’s shares of common stock (the “Common Stock”) are traded primarily on the New York Stock Exchange under the symbol “TY.” The closing market price of the Common Stock on February 28, 2015 was $22.01 per share.

The Fund invests primarily for the longer term, and the Fund’s objective is to produce future growth of both capital and income while providing reasonable current income. The Fund may invest in all types of securities. See “Investment Objective and Other Policies and Related Risks.” No assurance can be given that the Fund’s investment objective will be realized. The Fund’s investment manager is Columbia Management Investment Advisers, LLC (“Columbia Management” or the “Manager”).

This Prospectus applies to all shares of Common Stock purchased under the Fund’s various investment plans and to all shares of Common Stock issued upon exercise of the Fund’s outstanding Warrants. See “Investment Plans and Other Services.” The shares of Common Stock covered by this Prospectus also may be issued from time to time by the Fund to acquire the assets of personal holding companies, private investment companies or publicly owned investment companies. See “Issuance of Shares in Connection with Acquisitions.”

This Prospectus sets forth the information that a prospective investor should know about the Fund before investing. Investors are advised to read this Prospectus carefully and to retain it for future reference. Additional information about the Fund, including a Statement of Additional Information (“SAI”) dated May 1, 2015, has been filed with the Securities and Exchange Commission. The SAI, as well as the Fund’s most recent Annual and Semi-Annual Reports are also available upon request and without charge by writing to Columbia Management Investment Services Corp. (“CMISC” or the “Service Agent”), the Fund’s stockholder servicing, dividend paying and transfer agent, at P.O. Box 8099, Boston, Massachusetts 02266-8099 or calling the Service Agent at the telephone number listed above. Investors may also write or call the Service Agent in order to request other available information or to make stockholder inquiries. The SAI is incorporated herein by reference in its entirety and its table of contents appears on page 24 of this Prospectus. The 2014 Annual Report contains financial statements of the Fund for the year ended December 31, 2014, which are incorporated by reference into the SAI. The SAI, as well as the Fund’s most recent Annual and Semi-Annual Reports are also available at columbiathreadneedle.com/us. The website references in this Prospectus are inactive textual references and information contained in or otherwise accessible through this website does not form a part of this Prospectus. The Securities and Exchange Commission maintains a website (www.sec.gov) that contains the Prospectus, SAI, material incorporated by reference, and other information filed electronically by the Fund.

Common Stock

($0.50 par value)

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Summary of Fund Expenses

The following table illustrates the expenses and fees that the Fund expects to incur and that you can expect to bear as a holder of the Fund’s Common Stock. The total annual expenses in the fee and expense table below are based on expenses incurred during the Fund’s most recently completed fiscal year and are expressed as a percentage (expense ratio) of the Fund’s average net assets during the period. The expense ratio has been adjusted to reflect current fee arrangements, but has not been adjusted to reflect the Fund’s assets as of a different period or point in time, as asset levels will fluctuate. In general, the Fund’s annual operating expense ratio will increase as the Fund’s assets decrease, such that the Fund’s actual expense ratio may be higher than the expense ratio presented in the table.

Columbia Management provides investment management services for a fee, as disclosed in the fee table below. Columbia Management also serves as administrative services agent for the Fund. Columbia Management charges a fee for administrative services provided to the Fund (reflected in the Fund’s “Other Expenses” in the fee table below). Please see the “Management of the Fund” section of the prospectus for a description of such fees.

The following example illustrates the costs you would pay on a $1,000 investment, assuming a 5% annual return (includes the impact of dividends on preferred stock):

If dividends on the Fund’s Preferred Stock (as defined herein) were not included, the total expenses incurred for 1, 3, 5 and 10 years will be $6, $18, $31 and $70.

The purpose of the table above is to assist you in understanding the various costs and expenses you will bear directly or indirectly. For more complete descriptions of the various costs and expenses, see “Management of the Fund” and “Investment Plans and Other Services — Automatic Dividend Investment and Cash Purchase Plan.”

The example does not represent actual costs, which may be more or less than those shown. Moreover, the Fund’s actual rate of return may be more or less than the hypothetical 5% return shown in the example.

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Prospectus Summary

The following is qualified in its entirety by the more detailed information included elsewhere in this Prospectus.

This Prospectus applies to shares of Common Stock of the Fund. The Fund invests primarily for the longer term and has no charter restrictions with respect to such investments. The Fund’s objective is to produce future growth of both capital and income while providing reasonable current income. There can be no assurance that this objective will be achieved. With respect to the Fund’s investments, assets may be held in cash or invested in all types of securities in whatever amounts or proportions the Manager believes is best suited to current and anticipated economic and market conditions. These may include preferred and common stocks, debt securities, repurchase agreements, derivatives, including futures contracts, illiquid securities and securities of foreign issuers (including emerging markets issuers), each of which could involve certain risks. The Fund also employs leverage through its outstanding shares of preferred stock. See “Investment Objective and Other Policies and Related Risks.”

Columbia Management Investment Advisers, LLC, a wholly owned subsidiary of Ameriprise Financial, Inc., is the investment manager of the Fund. Columbia Management also serves as administrative services agent to the Fund and provides or compensates others to provide accounting, treasury and other services to the Fund and the other Columbia funds.

The management fee rate for the year ended December 31, 2014 was equivalent to 0.36% of the Fund’s average daily net assets. See “Management of the Fund” for more information.

Shares of Common Stock covered by this Prospectus may be purchased from time to time by the Service Agent, the Plan service agent for the Automatic Dividend Investment and Cash Purchase Plans, Individual Retirement Accounts (“IRAs”) and Retirement Plans for Self-Employed Individuals, Partnerships and Corporations (collectively, the “Plans”), as directed by participants, and may be sold from time to time by the Service Agent for participants in Systematic Withdrawal Plans. See “Investment Plans and Other Services.” Shares will be purchased for the Plans on the New York Stock Exchange or elsewhere when the market price of the Common Stock is equal to or less than its net asset value, and any brokerage commissions applicable to such purchases will be charged pro rata to the Plan participants. Shares will be purchased for the Plans from the Fund at net asset value when the net asset value is lower than the market price, all as more fully described in this Prospectus.

The Board re-approved the Fund’s stock repurchase program for 2015. Identical to the Fund’s 2014 stock repurchase program, the Fund’s 2015 stock repurchase program allows the Fund to repurchase up to 5% of the Fund’s outstanding Common Stock during the year directly from Stockholders and in the open market, provided that, with respect to shares purchased in the open market, the excess of the net asset value of a share of Common Stock over its market price (the discount) is greater than 10%. During 2014, the Fund purchased 885,692 shares of Common Stock in the open market. The intent of the stock repurchase program is, among other things, to moderate the growth in the number of shares of Common Stock outstanding, increase the NAV of the Fund’s outstanding shares, reduce the dilutive impact on stockholders who do not take capital gains distributions in additional shares and increase the liquidity of the Fund’s Common Stock in the marketplace.

The Fund

The Fund is a Maryland corporation formed in 1929 by the consolidation of two predecessor corporations. It is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as a diversified management investment company of the closed-end type. The Fund’s Common Stock is listed on the New York Stock Exchange under the symbol “TY.” The average weekly trading volume on that and other exchanges during 2014 was 246,678 shares. The Fund’s Common Stock has historically been traded on the market at less than net asset value. As of February 28, 2015, the Fund had 60,608,791 shares of Common Stock outstanding and net assets attributable to Common Stock of $1,552,752,750.

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Financial Highlights

The Fund’s financial highlights for the three most recent fiscal years presented on the following pages have been derived from the financial statements audited by PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm. Financial highlights for prior fiscal years were derived from the financial statements audited by other auditors. The information below, which is derived from the financial and accounting records of the Fund, should be read in conjunction with the financial statements and notes contained in the Fund’s 2014 Annual Report, which may be obtained from CMISC as provided in this Prospectus.

“Per Share Operating Performance” data is designed to allow you to trace the operating performance, on a per Common Stock share basis, from the beginning net asset value to the ending net asset value so that you can understand what effect the individual items have on your investment, assuming it was held throughout the year. Generally, the per share amounts are derived by converting the actual dollar amounts incurred for each item, as disclosed in the financial statements, to their equivalent per Common Stock share amounts, using average shares outstanding during the period.

The total investment return based on market value measures the Fund’s performance assuming you purchased shares of the Fund at the market value as of the beginning of the year, invested dividends and capital gains paid as provided for in the Fund’s Automatic Dividend Investment and Cash Purchase Plan, and then sold your shares at the closing market value per share on the last day of the year. The computation does not reflect any sales commissions you may incur in purchasing or selling shares of the Fund. The total investment return based on net asset value is similarly computed except that the Fund’s net asset value is substituted for the corresponding market value.

The ratios of expenses and net investment income to average net assets for Common Stock for the periods presented do not reflect the effect of dividends paid to holders of the Fund’s $2.50 cumulative preferred stock (the “Preferred Stock”).

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PER SHARE OPERATING PERFORMANCE, TOTAL INVESTMENT RETURN, RATIOS AND SUPPLEMENTAL DATA

(for a share of Common Stock outstanding throughout each year)

Notes to Financial Highlights

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SENIOR SECURITIES — $2.50 CUMULATIVE PREFERRED STOCK

The following information is being presented with respect to the Fund’s $2.50 cumulative Preferred Stock. The first column presents the number of shares of Preferred Stock outstanding at the end of each year presented. “Year-End Asset Coverage Per Share” represents the total amount of net assets of the Fund in relation to each share of Preferred Stock outstanding as of the end of the respective year. The “Involuntary Liquidation Preference Per Share” is the amount each share of Preferred Stock would be entitled to upon involuntary liquidation of these shares.

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Capitalization at February 28, 2015

Trading and Net Asset Value Information

The following table shows the high and low closing prices of the Fund’s Common Stock on the composite tape for issues listed on the New York Stock Exchange for each calendar quarter since the beginning of 2013, as well as the net asset values and the range of the percentage discounts to net asset value per share that correspond to such prices.

The Fund’s Common Stock has historically been traded on the market at less than net asset value. The closing market price, net asset value and percentage discount to net asset value per share of the Fund’s Common Stock on March 31, 2015 were $21.69, $25.12 and 13.65%.

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Investment Objective and Other Policies and Related Risks

The Fund is a Maryland corporation formed in 1929 by the consolidation of two predecessor corporations. It is registered under the 1940 Act as a diversified management investment company of the closed-end type.

The Fund invests primarily for the longer term and has no charter restrictions with respect to such investments. The Fund’s investment objective is to produce future growth of both capital and income while providing reasonable current income. There can be no assurance that this objective will be achieved. With respect to the Fund’s investments, assets may be held in cash or invested in all types of securities, that is, in common stocks, bonds, convertible bonds (including high yield instruments), debentures, notes, preferred and convertible preferred stocks, rights, derivatives (including futures contracts), and other securities, in whatever amounts or proportions the Manager believes best suited to current and anticipated economic and market conditions. Derivatives may be used to produce incremental earnings, to hedge existing positions, to maintain investment efficiency, or to increase flexibility. Fixed income and convertible securities may be rated below investment grade or be deemed to have a comparable rating. The Fund may invest in fixed income securities of any maturity and does not seek to maintain a particular dollar-weighted average maturity. The Fund may invest up to 25% of its net assets in foreign investments, including those in emerging markets. The Fund also employs leverage through its outstanding shares of preferred stock.

The Fund’s present investment policies, in respect to which it has freedom of action, are:

(1) it keeps investments in individual issuers within the limits permitted diversified companies under the 1940 Act (i.e., 75% of its total assets must be represented by cash items, government securities, securities of other investment companies, and securities of other issuers which, at the time of investment, do not exceed 5% of the Fund’s total assets at market value in the securities of any issuer and do not exceed 10% of the voting securities of any issuer);

(2) it does not make investments with a view to exercising control or management except that, as of the date hereof, it has an investment in Seligman Data Corp., the former shareholder servicing agent for the Fund;

(3) it ordinarily does not invest in other investment companies, but it may purchase up to 3% of the voting securities of such investment companies, provided purchases of securities of a single investment company do not exceed in value 5% of the total assets of the Fund and all investments in investment company securities do not exceed 10% of total assets; and

(4) it has no fixed policy with respect to portfolio turnover and purchases and sales in the light of economic, market and investment considerations. The portfolio turnover rates for the ten fiscal years ended December 31, 2014 are shown under “Financial Highlights.”

The foregoing investment objective and policies may be changed by the Fund’s Board of Director’s (the “Board”) without stockholder approval, unless such a change would change the Fund’s status from a “diversified” to a “non-diversified” company under the 1940 Act.

The Fund has fundamental policies relating to the issuance of senior securities, the borrowing of money, the underwriting of securities of other issuers, the concentration of investments in a particular industry or groups of industries, the purchase or sale of real estate, the purchase or sale of commodities or commodity contracts, and the making of loans. These policies may not be changed without a vote of stockholders. A more detailed description of the Fund’s investment policies, including a list of those restrictions on the Fund’s investment activities which cannot be changed without such a vote, appears in the SAI. Within the limits of these fundamental policies, the Manager has reserved freedom of action.

The Fund may not invest 25% or more of its total assets in securities of companies in any one industry. The Fund may, however, invest a substantial percentage of its assets in certain industries or economic sectors believed to offer good investment opportunities. If an industry or economic sector in which the Fund is invested falls out of favor, the Fund’s performance may be negatively affected.

Active Management Risk. The Fund is actively managed and its performance therefore will reflect, in part, the ability of the portfolio managers to make investment decisions that will achieve the Fund’s investment objective. Due to its active management, the Fund could underperform its benchmark index and/or other funds with a similar investment objective and/or strategies.

Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt securities, such as interest rate risk (the risk of losses attributable to changes in interest rates) and credit risk (the risk that the issuer of a debt security will default or otherwise become unable, or be perceived to be unable or unwilling, to honor a financial obligation, such as making payments to the Fund when due). Convertible securities also react to changes in the value of the common stock into which they convert, and are thus subject to market risk (the risk that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise). Because the value of a convertible security can be influenced by both interest rates and the common stock’s market movements, a convertible security generally is not as sensitive to interest rates as a similar debt security, and generally will not vary in value in response to other factors to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities would typically be paid

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before the company’s common stockholders but after holders of any senior debt obligations of the company. The Fund may be forced to convert a convertible security before it otherwise would choose to do so, which may decrease the Fund’s return.

Credit Risk. The value of fixed-income securities may decline if the issuer of the security defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Various factors could affect the actual or perceived willingness or ability of the issuer to make timely interest or principal payments, including changes in the financial condition of the issuer or in general economic conditions. Fixed-income securities backed by an issuer’s taxing authority may be subject to legal limits on the issuer’s power to increase taxes or otherwise to raise revenue, or may be dependent on legislative appropriation or government aid. Certain fixed-income securities are backed only by revenues derived from a particular project or source, rather than by an issuer’s taxing authority, and thus may have a greater risk of default. Rating agencies assign credit ratings to certain fixed-income securities to indicate their credit risk. Lower quality or unrated securities held by the Fund may present increased credit risk as compared to higher-rated securities. Non-investment grade fixed-income securities (commonly called “high-yield” or “junk”) are subject to greater price fluctuations and are more likely to experience a default than investment grade securities and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated fixed-income securities, or if the ratings of securities held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual.

Derivatives Risk. Derivatives are financial instruments whose value depends on, or is derived from, the value of other underlying assets. Losses involving derivative instruments may be substantial, because a relatively small price movement in the underlying security(ies), instrument, commodity, currency or index may result in a substantial loss for the Fund. In addition to the potential for increased losses, the use of derivative instruments may lead to increased volatility for the Fund. Derivative investments will typically increase the Fund’s exposure to principal risks to which it is otherwise exposed, and may expose the Fund to additional risks. Depending on the type and purpose of the Fund’s derivative investments, these risks may include: correlation risk (there may be an incomplete correlation between the hedge and the opposite position, which is related to hedging risk), counterparty risk (the counterparty to the instrument may not perform or be able to perform in accordance with the terms of the instrument), leverage risk (losses from the derivative instrument may be greater than the amount invested in the derivative instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), and/or liquidity risk (it may not be possible for the Fund to liquidate the instrument at an advantageous time or price), each of which may result in significant losses for the Fund.

Derivatives Risk/Futures Contracts Risk. The use of futures contracts is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. A futures contract is a sales contract between a buyer (holding the “long” position) and a seller (holding the “short” position) for an asset with delivery deferred until a future date. The buyer agrees to pay a fixed price at the agreed future date and the seller agrees to deliver the asset. The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. The liquidity of the futures markets depends on participants entering into off-setting transactions rather than making or taking delivery. To the extent participants decide to make or take delivery, liquidity in the futures market could be reduced. In addition, futures exchanges often impose a maximum permissible price movement on each futures contract for each trading session. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Moreover, to the extent the Fund engages in futures contracts on foreign exchanges, such exchanges may not provide the same protection as U.S. exchanges. The loss that the Fund may incur in entering into futures contracts may exceed the amount of the premium paid and may be potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally involved in futures trading, a relatively small price movement in a futures contract may result in substantial losses for the Fund. Investment in these instruments involves risks, including counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains) and pricing risk (the risk that the instrument may be difficult to value), each of which may result in significant losses for the Fund.

Emerging Market Securities Risk. Securities issued by foreign governments or companies in emerging market countries are more likely to have greater exposure to the risks of investing in foreign securities that are described in Foreign Securities Risk. In addition, emerging market countries are more likely to experience instability resulting, for example, from rapid changes or developments in social, political, economic or other conditions. Their economies are usually less mature and their securities markets are typically less developed with more limited trading activity (i.e., lower trading volumes and less liquidity) than more developed countries. Emerging market securities tend to be more volatile than securities in more developed markets. Many emerging market countries are heavily dependent on international trade and have fewer trading partners, which makes them more sensitive to world commodity prices and economic downturns in other countries. Some emerging market countries have a higher risk of currency devaluations, and some of these countries may experience periods of high inflation or rapid changes in inflation rates and may have hostile relations with other countries.

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Foreign Securities Risk. Investments in or exposure to foreign securities involve certain risks not associated with investments in or exposure to securities of U.S. companies. For example, foreign markets can be extremely volatile. The performance of the Fund may be negatively impacted by fluctuations in a foreign currency’s strength or weakness relative to the U.S. dollar. Foreign securities may also be less liquid than securities of U.S. companies so that the Fund may, at times, be unable to sell foreign securities at desirable times or prices. Brokerage commissions, custodial costs and other fees are also generally higher for foreign securities. The Fund may have limited or no legal recourse in the event of default with respect to certain foreign securities, including those issued by foreign governments. In addition, foreign governments may impose potentially confiscatory withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. Other risks include: possible delays in the settlement of transactions or in the payment of income; generally less publicly available information about foreign companies; the impact of economic, political, social, diplomatic or other conditions or events; possible seizure, expropriation or nationalization of a company or its assets or the assets of a particular investor or category of investors; possible imposition of currency exchange controls; accounting, auditing and financial reporting standards that may be less comprehensive and stringent than those applicable to domestic companies; the imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country; and the generally less stringent standard of care to which local agents may be held in the local markets. In addition it may be difficult to obtain reliable information about the securities and business operations of certain foreign issuers. Governments or trade groups may compel local agents to hold securities in designated depositories that are not subject to independent evaluation. The less developed a country’s securities market is, the greater the level of risks. The risks posed by sanctions against a particular foreign country, its nationals or industries or businesses within the country may be heightened to the extent the Fund invests significantly in the affected country or region or in issuers from the affected country that depend on global markets.

Frequent Trading Risk. The portfolio managers may actively and frequently trade investments in the Fund’s portfolio to carry out its investment strategies. Frequent trading can mean higher brokerage and other transaction costs, which could reduce the Fund’s return. The trading costs associated with portfolio turnover may adversely affect the Fund’s performance.

High-Yield Securities Risk. Securities rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated securities of comparable quality tend to be more sensitive to credit risk than higher-rated securities and may experience greater price fluctuations in response to perceived changes in the ability of the issuing entity or obligor to pay interest and principal when due than to changes in interest rates. These investments are generally more likely to experience a default than higher-rated securities. High-yield securities are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal. These securities typically pay a premium — a higher interest rate or yield — because of the increased risk of loss, including default. High-yield securities may require a greater degree of judgment to establish a price, may be difficult to sell at the time and price the Fund desires, may carry high transaction costs, and also are generally less liquid than higher-rated securities. The securities ratings provided by third party rating agencies are based on analyses by these ratings agencies of the credit quality of the securities and may not take into account every risk related to whether interest or principal will be timely repaid. In adverse economic and other circumstances, issuers of lower-rated securities are more likely to have difficulty making principal and interest payments than issuers of higher-rated securities.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt securities tend to fall, and if interest rates fall, the values of debt securities tend to rise. Changes in the value of a debt security usually will not affect the amount of income the Fund receives from it but will usually affect the value of the Fund’s shares. In general, the longer the maturity or duration of a debt security, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. Similarly, a period of rising interest rates may negatively impact the Fund’s performance. Actions by governments and central banking authorities can result in increases in interest rates. Such actions may negatively affect the value of fixed-income securities held by the Fund, resulting in a negative impact on the Fund’s performance and NAV.

Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly, and therefore, the value of its securities may decline, which would negatively affect the Fund’s performance. Poor performance may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters or other events, conditions or factors.

Leverage and its Risks: Senior securities issued or money borrowed to raise funds for investment have a prior fixed dollar claim on the Fund’s assets and income. Any gain in the value of securities purchased or income received in excess of the cost of the amount borrowed or interest or dividends payable causes the net asset value of the Fund’s Common Stock or the income available to it to increase more than otherwise would be the case. Conversely, any decline in the value of securities purchased or income received on them that is less than the asset or income claims of the senior securities or cost of borrowed money causes the net asset value of the Common Stock or income available to it to decline more sharply than would be the case if there were no prior

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claim. Funds obtained through senior securities or borrowings thus create investment opportunity, but they also increase exposure to risk. This influence ordinarily is called “leverage.” As of February 28, 2015, the only senior securities of the Fund outstanding were 752,740 shares of its $2.50 Cumulative Preferred Stock, $50 par value. The dividend rate as of February 28, 2015 on the Preferred Stock was $2.50 per annum payable quarterly. Based on the net asset value of the Fund’s Common Stock on February 28, 2015, the Fund’s portfolio requires an annual return of 0.12% in order to cover dividend payments on the Preferred Stock. For a description of such payments, see “Description of Capital Stock.” The following table illustrates the effect of leverage relating to presently outstanding Preferred Stock on the return available to a holder of the Fund’s Common Stock.

The purpose of the table above is to assist you in understanding the effects of leverage caused by the Fund’s Preferred Stock. The percentages appearing in the table are hypothetical. Actual returns may be greater or less than those shown above.

The use of leverage creates certain risks for the Fund’s Common Stockholders, including the greater likelihood of higher volatility of the Fund’s return, its net asset value and the market price of the Fund’s Common Stock. Changes in the value of the Fund’s total assets will have a disproportionate effect on the net asset value per share of Common Stock because of the Fund’s leveraged assets. For example, if the Fund was leveraged equal to 50% of the Fund’s Common Stock equity, it would show an approximately 1.5% increase or decline in net asset value for each 1% increase or decline in the value of its total assets. An additional risk of leverage is that the cost of the leverage plus applicable Fund expenses may exceed the return on the transactions undertaken with the proceeds of the leverage, thereby diminishing rather than enhancing the return to the Fund’s Common Stockholders. These risks generally would make the Fund’s return to Common Stockholders more volatile. The Fund also may be required to sell investments in order to make interest payments on borrowings used for leverage when it may be disadvantageous to do so. Because the fees received by the Manager are based on the net assets of the Fund (including assets attributable to the Fund’s Preferred Stock and borrowings that may be outstanding), the Manager has a financial incentive for the Fund to maintain the Preferred Stock or use borrowings, which may create a conflict of interest between the Manager, on the one hand, and the Common Stockholders on the other hand.

Market Risk. Market risk refers to the possibility that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise. Security values may fall or fail to rise because of a variety of actual or perceived factors affecting an issuer (e.g., an unfavorable earnings report), the industry or sector in which it operates, or the market as a whole, which may reduce the value of an investment in the Fund. Accordingly, an investment in the Fund could lose money over short or long periods. The market values of the securities the Fund holds can be affected by changes or perceived changes in U.S. or foreign economies and financial markets, and the liquidity of these securities, among other factors. Although equity securities generally tend to have greater price volatility than debt securities, under certain market conditions, debt securities may have comparable or greater price volatility. In addition, common stock prices may be sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

Preferred Stock Risk. Preferred stock is a type of stock that generally pays dividends at a specified rate and that has preference over common stock in the payment of dividends and the liquidation of assets. Preferred stock does not ordinarily carry voting rights. The price of a preferred stock is generally determined by earnings, type of products or services, projected growth rates, experience of management, liquidity, and general market conditions of the markets on which the stock trades. The most significant risks associated with investments in preferred stock include issuer risk, market risk and interest rate risk (i.e., the risk of losses attributable to changes in interest rates).

Quantitative Model Risk. The Fund may use quantitative methods to select investments. Securities or other investments selected using quantitative methods may perform differently from the market as a whole or from their expected performance for many reasons, including factors used in building the quantitative analytical framework, the weights placed on each factor, and changing sources of market returns, among others. Any errors or imperfections in the Fund portfolio manager’s quantitative analyses or models, or in the data on which they are based, could adversely affect the portfolio manager’s effective use of such analyses or models, which in turn could adversely affect the Fund’s performance. It is not possible or practicable for a manager to factor all relevant, available data into quantitative model forecasts and/or trading decisions. Quantitative managers will use their discretion to determine what data to gather with respect to an investment strategy and what data the models will take into account to produce forecasts that may have an impact on ultimate trading decisions. Shareholders should be aware that there is no guarantee that a quantitative manager will use any specific data or type of data in making trading decisions on behalf of the Fund, nor is there any guarantee that the data actually utilized in generating forecasts or making trading decisions on behalf of the Fund will be the most accurate data available or free from errors. There can be no assurance that these methodologies will enable the Fund to achieve its objective.

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Management of the Fund

Columbia Management Investment Advisers, LLC is located at 225 Franklin Street, Boston, MA 02110 and serves as investment adviser to the Columbia Funds, which includes the Fund. Columbia Management is a registered investment adviser and a wholly-owned subsidiary of Ameriprise Financial. Columbia Management’s management experience covers all major asset classes, including equity securities, fixed-income securities and money market instruments. In addition to serving as an investment adviser to traditional mutual funds, exchange-traded funds and another closed-end fund, Columbia Management acts as an investment adviser for itself, its affiliates, individuals, corporations, retirement plans, private investment companies and financial intermediaries.

Under an Investment Management Services Agreement between Columbia Management and the Fund (the “Management Agreement”), the Manager determines on behalf of the Fund which securities will be purchased, held or sold. The annual management fee rate charged by the Manager is 0.355% of the Fund’s average daily net assets. The management fee for the year ended December 31, 2014 was 0.36% of the Fund’s average daily net assets.

Under an Administrative Services Agreement between the Fund and Columbia Management, Columbia Management provides, or compensates others to provide, administrative services, including accounting, treasury and other services to the Fund for a fee at an annual rate equal to a percentage of the Fund’s average daily net assets as follows:

For the year ended December 31, 2014, administrative services were provided to the Fund by Columbia Management, for which the Fund paid to Columbia Management 0.06% of the Fund’s average daily net assets.

The Management Agreement was originally entered into on November 7, 2008 and will continue in full force and effect and from year to year thereafter if such continuance is approved in the manner required by the 1940 Act (i.e., by a vote of a majority of the Board or of the outstanding voting securities of the Fund and by a vote of a majority of Fund’s directors who are not parties to the Management Agreement or “interested persons” (as defined in the 1940 Act) of any such party). The Management Agreement may be terminated by either the Fund or Columbia Management at any time by giving the other party 60 days’ written notice of such intention to terminate, provided that any termination shall be made without the payment of any penalty, and provided further that termination may be effected either by the Board or by a vote of the majority of the outstanding voting shares of the Fund. The Management Agreement will terminate automatically in the event of its assignment, as such term is defined in the 1940 Act.

Under the Management Agreement, the Fund also pays taxes, brokerage commissions and nonadvisory expenses, which include custodian fees and charges; fidelity bond premiums; certain legal fees; registration fees for shares, as necessary; consultants’ fees; compensation of Board members, officers and employees not employed by the Manager or its affiliates; corporate filing fees; organizational expenses; expenses incurred in connection with lending securities; interest and fee expense related to the Fund’s participation in inverse floater structures; and expenses properly payable by the Fund, approved by the Board.

A discussion regarding the basis for the Board’s approval of the Management Agreement is available in the Fund’s Semi-Annual Report for the period ending June 30, 2014.

Portfolio Managers. The portfolio managers responsible for the Fund’s day-to-day management are:

Brian M. Condon, Co-Portfolio Manager

Peter Albanese, Co-Portfolio Manager

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Yan Jin, Co-Portfolio Manager

David L. King, Co-Portfolio Manager

The SAI provides additional information about portfolio manager compensation, management of other accounts and ownership of shares in the Fund.

Administration Services. Columbia Management Investment Advisers, LLC serves as administrator to the Fund and is located at 225 Franklin Street, Boston, Massachusetts 02110. Columbia Management provides or compensates others to provide administrative services to the Fund and the other funds in the Columbia Family of Funds.

Board Services Corporation. The Fund has an agreement with Board Services Corporation (“Board Services”) located at 901 Marquette Avenue South, Suite 2810, Minneapolis, MN 55402. This agreement sets forth the terms of Board Services’ responsibility to serve as an agent of the Columbia funds, which includes the Fund, for purposes of administering the payment of compensation to each independent Board member, to provide office space for use by the funds and their boards, and to provide any other services to the boards or the independent members, as may be reasonably requested.

Transfer, Stockholder Service and Dividend Paying Agent. Columbia Management Investment Services Corp. is the Fund’s transfer, stockholder service and dividend paying agent. CMISC is located at 225 Franklin Street, Boston, Massachusetts 02110.

Independent Registered Public Accounting Firm. PricewaterhouseCoopers LLP is the Fund’s independent registered public accounting firm. Their address is 225 South 6th Street, Minneapolis, MN 55402.

LEGAL PROCEEDINGS

Ameriprise Financial, the parent company of Columbia Management (the Fund’s investment adviser), and certain of its affiliates have historically been involved in a number of legal, arbitration and regulatory proceedings, including routine litigation, class actions, and governmental actions, concerning matters arising in connection with the conduct of their business activities. Ameriprise Financial believes that the Fund is not currently the subject of, and that neither Ameriprise Financial nor any of its affiliates are the subject of, any pending legal, arbitration or regulatory proceedings that are likely to have a material adverse effect on the Fund or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Fund. Information regarding certain pending and settled legal proceedings may be found in the Fund’s stockholder reports and in the SAI.

Additionally, Ameriprise Financial is required to make 10-Q, 10-K and, as necessary, 8-K filings with the Securities and Exchange Commission on legal and regulatory matters that relate to Ameriprise Financial and its affiliates. Copies of these filings may be obtained by accessing the SEC website at www.sec.gov.

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Description of Capital Stock

(a) Dividend Rights: Holders of Common Stock (“Common Stockholders”) are entitled to receive dividends only if and to the extent declared by the Fund’s Board and only after (i) such provisions have been made for working capital and for reserves as the Board may deem advisable, (ii) full cumulative dividends at the rate of $0.625 per share per quarterly dividend period have been paid on the Preferred Stock for all past quarterly periods and have been provided for the current quarterly period, and (iii) such provisions have been made for the purchase or for the redemption (at a price of $55 per share) of the Preferred Stock as the Board may deem advisable. In any event, no dividend may be declared upon the Common Stock unless, at the time of such declaration, the net assets of the Fund, after deducting the amount of such dividend and the amount of all unpaid dividends declared on the Preferred Stock, shall be at least equal to $100 per outstanding share of Preferred Stock. The equivalent figure was $2,112.80 at February 28, 2015.

(b) Voting Rights: The Preferred Stock is entitled to two votes and the Common Stock is entitled to one vote per share at all meetings of stockholders. In the event of a default in payments of dividends on the Preferred Stock equivalent to six quarterly dividends, the Preferred Stockholders are entitled, voting separately as a class to the exclusion of Common Stockholders, to elect two additional directors, such right to continue until all arrearages have been paid and current Preferred Stock dividends are provided for. Notwithstanding any provision of law requiring any action to be taken or authorized by the affirmative vote of the holders of a designated portion of all the shares or of the shares of each class, such action shall be effective if taken or authorized by the affirmative vote of a majority of the aggregate number of the votes entitled to vote thereon, except that a class vote of Preferred Stockholders is also required to approve certain actions adversely affecting their rights. Any change in the Fund’s fundamental policies may also be authorized by the vote of 67% of the votes present at a meeting if the holders of a majority of the aggregate number of votes entitled to vote are present or represented by proxy.

Consistent with the requirements of Maryland law, the Fund’s charter provides that the affirmative vote of two-thirds of the aggregate number of votes entitled to be cast thereon shall be necessary to authorize any of the following actions: (i) the dissolution of the Fund; (ii) a merger or consolidation of the Fund (in which the Fund is not the surviving corporation) with (a) an open-end investment company or (b) a closed-end investment company, unless such closed-end investment company’s articles of incorporation require a two-thirds or greater proportion of the votes entitled to be cast by such company’s stock to approve the types of transactions covered by clauses (i) through (iv) of this paragraph; (iii) the sale of all or substantially all of the assets of the Fund to any person (as such term is defined in the 1940 Act); or (iv) any amendment of the charter of this Fund which makes any class of the Fund’s stock a redeemable security (as such term is defined in the 1940 Act) or reduces the two-thirds vote required to authorize the actions listed in this paragraph. This could have the effect of delaying, deferring or preventing changes in control of the Fund.

(c) Liquidation Rights: In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Fund, after payment to the holders of Preferred Stock (“Preferred Stockholders”) of an amount equal to $50 per share plus dividends accrued or in arrears, the Common Stockholders are entitled, to the exclusion of the Preferred Stockholders, to share ratably in all the remaining assets of the Fund available for distribution to stockholders.

(d) Other Provisions: Common Stockholders do not have preemptive, subscription or conversion rights, and are not liable for further calls or assessments. The Fund’s Board (other than any directors who may be elected to represent Preferred Stockholders as described above) are classified as nearly as possible into three equal classes with a maximum three-year term so that the term of one class of directors expires annually. Such classification provides continuity of experience and stability of the Board while providing for the election of a portion of the Board each year. Such classification could have the effect of delaying, deferring or preventing changes in control of the Fund.

The Board may classify or reclassify any unissued stock of any class with or without par value (including Preferred Stock and Common Stock) into one or more classes of preference stock on a parity with, but not having preference or priority over, the Preferred Stock by fixing or altering before the issuance thereof the designations, preferences, voting powers, restrictions and qualifications of, the fixed annual dividends on, the times and prices of redemption, the terms of conversion, the number and/or par value of the shares and other provisions of such stock to the full extent permitted by the laws of Maryland and the Fund’s charter. Stockholder approval of such action is not required.

Description of Warrants

The Fund has issued and outstanding warrants (the “Warrants”). The Fund’s charter and Warrant certificates provide that each Warrant represents the right during an unlimited time to purchase one share of Common Stock at a price of $22.50 per share, subject to increase in the number of shares purchasable and adjustment of the price payable pursuant to provisions of the charter requiring such adjustments whenever the Fund issues any shares of Common Stock at a price less than the Warrant purchase price in effect immediately prior to issue. Each Warrant presently entitles the holder to purchase 24.19 shares of Common Stock at

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$0.93 per share. There were 8,148 Warrants outstanding at February 28, 2015. Fractional shares of Common Stock are not issued upon the exercise of Warrants. In lieu thereof, the Fund issues scrip certificates representing corresponding fractions of the right to receive a full share of Common Stock if exchanged by the end of the second calendar year following issuance or of the proceeds of the sale of a full share if surrendered during the next four years thereafter.

Computation of Net Asset Value

Net asset value of the Common Stock is determined daily, Monday through Friday, as of the close of regular trading on the New York Stock Exchange (normally, 4:00 p.m. Eastern time) each day the New York Stock Exchange is open for trading.

Net asset value per share of Common Stock is determined by dividing the current value of the assets of the Fund less its liabilities and the prior claim of the Preferred Stock by the total number of shares of Common Stock outstanding.

The Fund’s securities are valued as follows as of the close of business of the New York Stock Exchange. Securities traded on a securities exchange for which a last-quoted sales price is readily available are valued at the last-quoted sales price on the exchange where such security is primarily traded. Securities traded on a securities exchange for which a last-quoted sales price is not readily available are valued at the mean of the closing bid and asked prices, looking first to the bid and asked prices on the exchange where the security is primarily traded and, if none exist, to the over-the-counter market. Securities included in the NASDAQ National Market System are valued at the last-quoted sales price in this market. Securities included in the NASDAQ National Market System for which a last-quoted sales price is not readily available, and other securities traded over-the-counter but not included in the NASDAQ National Market System are valued at the mean of the closing bid and asked prices. Futures and options traded on major exchanges are valued at the last-quoted sales price on their primary exchange. Foreign securities traded outside the United States are generally valued as of the time their trading is complete, which is usually different from the close of the Exchange. Foreign securities quoted in foreign currencies are translated into U.S. dollars utilizing spot exchange rates at the close of regular trading on the Exchange. Occasionally, events affecting the value of securities occur between the time the primary market on which the securities are traded closes and the close of the Exchange. If events materially affect the value of securities, the securities will be valued at their fair value according to procedures decided upon in good faith by the Board. This occurs most commonly with foreign securities, but may occur in other cases. The fair value of a security is likely to be different from the quoted or published price. Short-term securities maturing more than 60 days from the valuation date are valued at the readily available market price or approximate market value based on current interest rates. Typically, short-term securities maturing in 60 days or less that originally had maturities of more than 60 days at acquisition date are valued at amortized cost using the market value on the 61st day before maturity. Short-term securities maturing in 60 days or less at acquisition date are valued at amortized cost. Amortized cost is an approximation of market value determined by systematically increasing the carrying value of a security if acquired at a discount, or reducing the carrying value if acquired at a premium, so that the carrying value is equal to maturity value on the maturity date. Securities without a readily available market price and securities for which the price quotations or valuations received from other sources are deemed unreliable or not reflective of market value are valued at fair value as determined in good faith by the Board. The Board is responsible for selecting methods it believes provide fair value. When possible, bonds are valued at an evaluated bid by a pricing service independent from the Fund. If a valuation of a bond is not available from a pricing service, the bond will be valued by a dealer knowledgeable about the bond if such a dealer is available.

Dividend Policy and Taxes

Distributions: Dividends are paid quarterly on the Preferred Stock and on the Common Stock in amounts representing substantially all of the net investment income earned each year by the Fund. Payments on the Preferred Stock are in a fixed amount, but payments on the Common Stock vary in amount, depending on investment income received and expenses of operation. In addition, substantially all of any taxable net gain realized on investments is paid to Common Stockholders at least annually.

For stockholder accounts established after June 1, 2007 directly with the Fund (which are serviced by the Service Agent), unless the Service Agent is otherwise instructed by you, distributions on the Common Stock are paid in book shares of Common Stock which are entered in your Fund account as “book credits.” You may also elect to receive distributions 75% in shares and 25% in cash, 50% in shares and 50% in cash, or 100% in cash. Any such election must be received by the Service Agent by the record date for a distribution. If you hold your shares of Common Stock through a financial intermediary (such as a broker), you should contact the financial intermediary to discuss your reinvestment and distribution options, as they may be different than as described above for accounts held directly with the Fund. A distribution is treated in the same manner for income tax purposes whether you receive it in cash or partly or entirely in shares. Elections received after a record date for a distribution will be effective in respect of the next distribution. Shares issued to you in respect of distributions will be at a price equal to the lower of: (i) the closing sale or bid price, plus applicable commission, of the Common Stock on the New York Stock Exchange on the ex-dividend date or (ii) the greater of net asset value per share of the Common Stock and 95% of the closing price of the Common

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Stock on the New York Stock Exchange on the ex-dividend date (without adjustment for the exercise of Warrants remaining outstanding). The issuance of Common Stock at less than net asset value per share will dilute the net asset value of all Common Stock outstanding at that time. Distributions received by you will have the effect of reducing the net asset value of the shares of the Fund by the amount of such distributions. If the net asset value of shares is reduced below your cost by a distribution, the distribution will be taxable as described below even though it is in effect a return of capital.

Distributions described above are subject to applicable law and the Board’s right to suspend, modify or terminate the distribution policy described below in the event the Board determines that such action would be in the best interests of the Fund. In addition, distributions will be made only when, as and if approved and declared and after paying dividends on the Preferred Stock and interest and required principal payments on borrowings, if any.

Pursuant to the Fund’s earned distribution policy, the Fund, subject to appropriate approval, intends to make quarterly distributions to Common Stockholders that are approximately equal to net investment income, less dividends payable on the Fund’s Preferred Stock. Capital gains, when available, are distributed to Common Stockholders along with the last income dividend of the calendar year. Dividends and other distributions to Stockholders are recorded on ex-dividend dates.

Taxes: The Fund intends to continue to qualify and elect to be treated as a regulated investment company under the Internal Revenue Code. As a regulated investment company, the Fund will generally not be subject to federal income taxes on its investment company taxable income and net capital gains realized during the year, if any, which it distributes to stockholders, provided that at least 90% of its investment company taxable income (which includes net short-term capital gains) is distributed to stockholders each year, among other requirements.

Qualification as a registered investment company does not, of course, involve governmental supervision of management or investment practices or policies. Investors should consult their own advisors for a complete understanding of the requirements the Fund must meet to qualify for such treatment. The information set forth below relates solely to certain U.S. Federal tax matters applicable to the Fund and its U.S. stockholders, and assumes that the Fund qualifies as a regulated investment company.

If for any year the Fund does not qualify as a regulated investment company, all of its taxable income (including its net capital gain) will be subject to tax at regular corporate rates without any deduction for distributions to stockholders. Such distributions will generally be taxable to the stockholders as qualified dividend income and generally will be eligible for the dividends received deduction in the case of corporate stockholders.

Dividends on Common Stock from the Fund’s ordinary income and net short-term capital gains are taxable to stockholders as ordinary income, whether received in cash or invested in additional shares. Dividends on Common Stock that the Fund reports as qualified dividend income will be taxed at a reduced rate to individuals (0%, 15%, or 20%). Qualified dividend income is, in general, dividend income from taxable domestic corporations and certain foreign corporations (generally foreign corporations incorporated in a possession of the United States or eligible for the benefits of a comprehensive tax treaty with the United States that meets certain requirements, or if the stock with respect to which such dividend is paid is readily tradable on an established securities market in the United States). The amount of dividends that may be designated as “qualified dividend income” by the Fund will generally be limited to the aggregate of the eligible dividends received by the Fund. In addition, the Fund must meet certain holding period requirements with respect to the shares on which the Fund received the eligible dividends, and the non-corporate U.S. stockholder must meet certain holding period requirements with respect to the Fund’s shares.

Distributions of net capital gains (i.e., the excess of net long-term capital gains over any net short-term capital losses) are taxable to stockholders as long-term capital gains, whether received in cash or invested in additional shares, regardless of how long you have held your shares. Individual stockholders will be subject to federal income tax on distributions report by the Fund as capital gains dividends at preferential rates (0%, 15%, or 20%). Net capital gain of a corporate shareholder is taxed at the same rate as ordinary income.

At December 31, 2014, the Fund had a capital loss carryforward for federal income purposes of $285,296,096, of which $285,296,096 expires in 2017. Provided no limitation on its utilization applies, such capital loss carryforward is available for offset against future taxable net gains.

Accordingly, no capital gain distributions are expected to be paid to stockholders until net capital gains have been realized in excess of the available capital loss carryforward. There is no assurance that the Fund will be able to utilize all of its capital loss carryforward before it expires.

Dividends declared in October, November or December of a calendar year, payable to stockholders of record on a specified date in such a month and paid in the following January will be treated as having been paid by the Fund and received by each stockholder on December 31 of such calendar year. Under this rule, therefore, stockholders may be taxed in one year on dividends actually received (or reinvested) in January of the following year.

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Distributions of Common Stock will generally be treated as if the stockholder received cash in amount equal to the cash that could have been received instead of such Common Stock. A stockholder will have a tax basis in the distributed shares of Common Stock equal to such amount and a stockholder’s holding period with respect to such Common Stock will begin the day following the distribution date for the Common Stock.

Any gain or loss you realize upon a sale of Common Stock (provided you are not a dealer in securities and hold the Common Stock as a capital asset) will generally be treated as a long-term capital gain or loss if you held your shares for more than one year and as a short-term capital gain or loss if you held your shares for one year or less. Long-term capital gain of a non-corporate U.S. stockholder is generally taxed at preferential rates (0%, 15%, or 20%). Net capital gain of a corporate stockholder is taxed at the same rate as ordinary income. However, if shares on which a capital gain distribution has been received are subsequently sold and such shares have been held for six months or less (after taking into account certain transactions that may affect the holding period of the shares), any loss realized will be treated as long-term capital loss to the extent of the long-term capital gain distribution. No loss will be allowed on the sale or other disposition of shares of Common Stock if, within a period beginning 30 days before the date of such sale or disposition and ending 30 days after such date, you acquire (such as through the Automatic Dividend Investment and Cash Purchase Plan), or enter into a contract or option to acquire, additional shares of the Fund or securities that are substantially identical to the Common Stock.

The repurchase of shares of Common Stock by the Fund generally will be a taxable transaction for federal income tax purposes, either as a sale as described above or, under certain circumstances, as a dividend. A repurchase of shares of Common Stock generally will be treated as a sale if the receipt of cash by the stockholder results in a “complete redemption” of the stockholder’s interest in the Fund or is “substantially disproportionate” or “not essentially equivalent to a dividend” with respect to the stockholder. In determining whether any of these tests have been met, shares actually owned and shares considered to be owned by the stockholder by reason of certain constructive ownership rules generally must be taken into account.

If none of the tests for sale treatment is met, the amount received by a stockholder on a repurchase of shares of Common Stock will be taxable to the stockholder as a dividend to the extent of such stockholder’s allocable share of the Fund’s current and accumulated earnings and profits. The excess of such amount received over the portion that is taxable as a dividend would constitute a nontaxable return of capital (to the extent of the stockholder’s adjusted tax basis in the shares of Common Stock repurchased), and any amount in excess of the stockholder’s adjusted tax basis would constitute taxable gain. Any remaining tax basis in the shares of Common Stock repurchased by the Fund will be transferred to any remaining shares of Common Stock held by such stockholder.

Certain high-income individuals (as well as estates and trusts) are subject to a 3.8% tax on net investment income. For individuals, the 3.8% tax applies to the lesser of (1) the amount (if any) by which the taxpayer’s modified adjusted gross income exceeds certain threshold amounts or (2) the taxpayer’s “net investment income.” Net investment income generally includes for this purpose dividends, including any capital gain dividends, paid by the Fund, and net capital grains recognized on the sale or disposition of Common Stock.

The Fund is required by federal law to withhold tax at the rate of 28% of taxable distributions and repurchase proceeds paid to you (including amounts paid to you in additional shares of Common Stock) if: you have not provided a correct taxpayer identification number (TIN) or have not certified to the Fund that withholding does not apply; the Internal Revenue Service (IRS) has notified the Fund that the TIN provided is incorrect according to its records; or the IRS informs the Fund that you are otherwise subject to backup withholding. Any amounts withheld may be refunded or credited against your U.S. federal income tax liability, if any, provided the required information is furnished to the IRS on a timely basis.

The Fund is subject to a 4% nondeductible excise tax on amounts required to be paid but not distributed under a prescribed formula. The formula requires payment to stockholders during a calendar year of distributions representing at least 98% of the Fund’s ordinary income for the calendar year, at least 98.2% of its net capital gain income realized during the one-year period ending on October 31 during such year, and all ordinary income and net capital gain income for prior years that was not previously distributed. The Fund intends to make sufficient distributions or deemed distributions of its ordinary income and net capital gain income prior to the end of each calendar year to avoid liability for the excise tax, but there is no assurance that the Fund will be able to do so.

The information provided above is only a summary of certain U.S. federal tax matters that may affect your investment in Common Stock. It is not intended as a substitute for careful tax planning. Your investment in Common Stock may have other tax implications. The information above does not apply to certain types of investors who may be subject to special rules, including foreign or tax-exempt investors or those holding Common Stock through a tax-advantaged account, such as a 401(k) plan or IRA. You should consult with your own tax advisor about the particular tax consequences to you of an investment in Common Stock, including the effect of any foreign, state and local taxes, and the effect of possible changes in applicable tax laws.

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Investment Plans and Other Services

AUTOMATIC DIVIDEND INVESTMENT AND CASH PURCHASE PLAN

The Automatic Dividend Investment and Cash Purchase Plan is available for any Common Stockholder who wishes to purchase additional shares of the Fund’s Common Stock with dividends or other cash payments on shares owned, with cash dividends paid by other corporations in which stock is owned or with cash funds. The tax treatment of dividends and capital gain distributions is the same whether you take them in cash or reinvest them to buy additional shares of the Fund’s Common Stock. Details of the services offered under the Plan are given in the Authorization Form for Automatic Dividend Investment and Cash Purchase Plan available at columbiathreadneedle.com/us. Under the Plan, you appoint the Fund as your purchase agent to receive or invest such dividends and cash funds forwarded by you for your accounts in additional shares of the Fund’s Common Stock (after deducting a service charge), as described under “Method of Purchase” below. Purchase orders received in connection with the Automatic Dividend and Cash Purchase Plan are generally priced one time per week, typically each Wednesday, subject to the potential for the suspension of such purchases as described below under “Method of Purchase.” Funds forwarded by you under the Plan should be made payable to Tri-Continental Corporation and mailed (if regular mail) to Tri-Continental Corporation, P.O. Box 8099, Boston, MA 02266-8099, and (if express mail) to Tri-Continental Corporation, c/o Boston Financial Data Services, Inc., 30 Dan Road, Suite 8099 Canton, MA 02021-2809. Checks for investment must be in U.S. dollars drawn on a domestic bank. You will be assessed a $15 fee for any checks rejected by your financial institution due to insufficient funds or other reasons. The Fund does not accept cash, credit card convenience checks, money orders, traveler’s checks, starter checks, third or fourth party checks, or other cash equivalents. You should direct all correspondence concerning the Plan to Tri-Continental Corporation, P.O. Box 8099, Boston, MA 02266-8099. At present, stockholders participating in the Fund’s Cash Purchase Plan will pay a service fee of $2.00 for each cash purchase transaction. There is no charge for Automatic Dividend Investment Plan. As of February 28, 2015, 13,371 stockholders, owning approximately 20,209,383 shares of Common Stock, were using the Plan. You may choose one or more of the services under the Plan and you may change your choices (or terminate participation) at any time by notifying CMISC in writing. The Plan may be amended or terminated by written notice to Planholders.

AUTOMATED CLEARING HOUSE SERVICE

The Automated Clearing House Service (“ACH”) enables you, if you are an Automatic Dividend Investment and Cash Purchase Planholder, to establish the ACH privilege that allows you to transfer money directly from your bank account by electronic funds transfer to be invested in additional shares of Common Stock for your account. ACH is a payment transfer system that connects US financial institutions. The ACH network acts as a central clearing facility for all electronic fund transfers transactions that occur nationwide. Important: Payments sent by electronic funds transfer, a bank authorization, or check that are not guaranteed may take up to 10 days or more to clear. If you request to sell shares before the purchase funds clear, this may cause your request to sell shares to fail to process if the requested amount includes unguaranteed funds. If you purchased your shares by check or from your bank account as an ACH transaction, the Fund may hold the proceeds of the sale when you sell those shares for a period of time after the receipt date of the funds.

SHARE KEEPING SERVICE

You may send certificates for shares of the Fund’s Common Stock to Tri-Continental Corporation to be placed in your account. Certificates should be sent to Tri-Continental Corporation, P.O. Box 8099, Boston, MA 02266-8099, in each case with a letter requesting that they be placed in your account. You should not sign the certificates and they should be sent by certified or registered mail. Return receipt is advisable; however, this may increase mailing time. When your certificates are received by the Service Agent, the shares will be entered in your Fund account as “book credits” and shown on the account statement received from the Service Agent. If you use the Share Keeping Service, you should keep in mind that you may need a stock certificate for delivery to a broker if you wish to sell shares. A certificate will be issued and sent to you on your written or telephone request to the Service Agent, usually within two business days of the receipt of your request. You should consider the time it takes for a letter to arrive at the Service Agent and for a certificate to be delivered to you by mail before you choose to use this service. During such time the market price of the Common Stock may fluctuate.

TAX-DEFERRED RETIREMENT PLANS

Shares of the Fund may be purchased for:

— Individual Retirement Accounts (IRAs) (available to current stockholders only);

— Savings Incentive Match Plans for Employees (SIMPLE IRAs);

— Simplified Employee Pension Plans (SEPs).

These types of plans may be established only upon receipt of a written application form. The Fund may register an IRA investment for which an account application has not been received as an ordinary taxable account.

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For more information, write Tri-Continental Corporation, P.O. Box 8099, Boston, MA 02266-8099. You may also telephone toll free by dialing (800) 345-6611 option 3 in the United States, (except holidays) between the hours of 9:00 a.m. and 6:00 p.m. Eastern time.

METHOD OF PURCHASE

Purchases will be made by the Fund from time to time on the New York Stock Exchange or elsewhere to satisfy cash purchase investments under the Automatic Dividend Investment and Cash Purchase Plan, tax-deferred retirement plans, and the investment plans noted above. Purchases will be suspended on any day when the closing price (or closing bid price if there were no sales) of the Common Stock on the New York Stock Exchange on the preceding trading day was higher than the net asset value per share (without adjustment for the exercise of Warrants remaining outstanding). If on the date shares are issuable to stockholders making Cash Purchase investments under the Plan (the “Issuance Date”), shares previously purchased by the Fund are insufficient to satisfy Cash Purchase investments and on the last trading day immediately preceding the Issuance Date the closing sale or bid price of the Common Stock is lower than or the same as the net asset value per share, the Fund will continue to purchase shares until a number of shares sufficient to cover all investments by stockholders has been purchased or the closing sale or bid price of the Common Stock becomes higher than the net asset value, in which case the Fund will issue the necessary additional shares. If on the last trading date immediately preceding the Issuance Date, the closing sale or bid price of the Common Stock was higher than the net asset value per share, and if shares of the Common Stock previously purchased on the New York Stock Exchange or elsewhere are insufficient to satisfy Cash Purchase investments, the Fund will issue the necessary additional shares from authorized but unissued shares of the Common Stock.

Shares will be issued on the dividend payable date or the Issuance Date at a price equal to the lower of (1) the closing sale or bid price, plus applicable commission, of the Common Stock on the New York Stock Exchange on the ex-dividend date or Issuance Date or (2) the greater of the net asset value per share of the Common Stock on such trading day (without adjustment for the exercise of Warrants remaining outstanding) and 95% of the closing sale or bid price of the Common Stock on the New York Stock Exchange on such trading day. The issuance of Common Stock at less than net asset value per share will dilute the net asset value of all Common Stock outstanding at that time. The Common Stock has historically been priced in the market at less than its net asset value per share (i.e. at a discount).

The net proceeds to the Fund from the sale of any shares of Common Stock to the Plans will be added to its general funds and will be available for investment. The Manager anticipates that investment of any proceeds, in accordance with the Fund’s investment objective and policies, will take up to thirty days from their receipt by the Fund, depending on market conditions and the availability of appropriate securities, but in no event will such investment take longer than six months. Pending such investment in accordance with the Fund’s objective and policies, the proceeds will be held in U.S. Government Securities (which term includes obligations of the United States Government, its agencies or instrumentalities) and other short-term money market instruments as well as affiliated money market funds.

If you are participating in the Automatic Dividend Investment and Cash Purchase Plan and your shares are held under the Plan in book credit form, you may terminate your participation in the Plan and receive a certificate for all or a part of your shares or have all or a part of your shares sold for you by the Fund and retain unsold shares in book credit form or receive a certificate for any shares not sold. Instructions must be signed by all registered stockholders and should be sent to Tri-Continental Corporation, P.O. Box 8099, Boston, MA 02266-8099. If you elect to have shares sold, you will receive the proceeds from the sale. Only participants whose shares are held in book credit form may elect upon termination of their participation in the Plan to have shares sold in the above manner. This will not affect the date on which your instruction to sell shares is actually processed.

HOW TO SELL SHARES

Accounts Held at a Broker-Dealer. If you hold shares through a broker-dealer and you wish to sell these shares, you must do so through such broker-dealer. If you have outstanding stock certificates, you must send your stock certificates to your broker-dealer in order to sell these shares. Please contact your broker-dealer directly for details on how to sell your shares.

Accounts Held Directly with the Fund. If your account is held directly with the Fund (direct accounts), you may sell your shares through the Service Agent. Orders to sell direct account shares may be placed with the Service Agent via mail or telephone, each as described below. Note that direct account sell orders received in “good form” (as described below) by and processed through the Service Agent are generally priced one time per week, typically each Wednesday. As such, for example, a sell order received in “good form” on a Thursday will not be processed (and your shares not sold) until the following Wednesday, provided that the New York Stock Exchange is open for business on such day. If you have outstanding stock certificates, you must send your stock certificates to the Service Agent (this is one of the requirements for your sell order to be considered received in “good form”). We recommend using registered mail when returning outstanding certificates for 2% of the current market value of the shares. The recommended insurance amount is based on the premium for a lost certificate bond in the event the certificate is lost in transit.

A sell order is in “good form” if the Service Agent has all of the information and documentation it deems necessary to effect your order. Certain sell orders processed through the Service Agent must be submitted in writing via letter of instructions signed by all

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registered stockholders with Medallion Signature Guarantee and any other required documents completed and attached. Please refer to Medallion Signature Guarantees for those circumstances when the request must be in writing. For the documents required for sell orders by corporations, agents, fiduciaries, surviving joint owners and other legal entities, call 800.345.6611. Written instructions to sell your direct account shares and any stock certificates should be sent to Tri-Continental Corporation, P. O. Box 8099, Boston, MA 02266-8099 or, for overnight delivery, to Tri-Continental Corporation, c/o Boston Financial Data Services, Inc. 30 Dan Road, Suite 8099, Canton, MA 02021-2809.

For direct account sell orders not required to be submitted in writing, you may call the Service Agent at (800) 345-6611, option 3 and speak to a stockholder service representative about selling your shares. Telephone orders may not be as secure as written orders. The Fund and its Service Agent will take reasonable steps to confirm that telephone instructions are genuine. For example, the Service Agent requires proof of your identification before acting on instructions received by telephone and may record telephone conversations. However, the Fund and its agents will not be responsible for any losses, costs or expenses resulting from an unauthorized telephone instruction when reasonable steps have been taken to confirm that telephone instructions are genuine. Telephone orders may be difficult to complete during periods of significant economic or market change or business interruption.

Proceeds from the sale of shares from your account in the Fund’s Common Stock may be sent to you by electronic funds transfer or by check to the address of record subject to certain limitations. See Limitations on Purchases and Sales under the Plans section above. Proceeds may be sent to your bank account by Federal Fund Wire (Fedwire) or via Automated Clearing House (ACH). If you wish to have your proceeds sent via Fedwire or ACH you must set up this feature prior to your request unless you are submitting your request in writing with a Medallion Signature Guarantee. The minimum amount that may be sent by Fedwire is $500. The Service Agent charges a fee for proceeds sent by Fedwire and may waive the fee for certain accounts. The receiving bank may charge an additional fee.

MEDALLION SIGNATURE GUARANTEE

The signatures of all stockholders must be guaranteed by an eligible guarantor institution including, but not limited to, the following: banks, credit unions, savings associations, brokers or dealers, provided that the institution participates in the Securities Transfer Association Medallion Program (STAMP), the Stock Exchange Medallion Program (SEMP) or the New York Stock Exchange Medallion Signature Program (MSP). A Medallion Signature Guarantee helps assure that a signature is genuine and not a forgery. The institution providing the Medallion Signature Guarantee is financially liable for the transaction if the signature is a forgery. Notarization by a notary public is not an acceptable signature guarantee. The Fund reserves the right to reject a signature guarantee in accordance with its standards and procedures.

A Medallion Signature Guarantee is required if:

1. Amount is over $100,000.

2. You want your check made payable to someone other than yourself.

3. Your address has changed within the last 30 days.

4. You want the check mailed to an address other than the address of record.

5. You want proceeds to be sent according to existing bank instructions not coded for outgoing ACH or wire, or to a bank account not on file.

6. You are the beneficiary of the account and the stockholder is deceased.*

7. You are changing legal ownership of your account (i.e., you are changing who is/are the legal owner(s) of your account).

* Other documentation may also be required. Please contact a representative.

CMISC reserves the right to require a Medallion Signature Guarantee and additional documentation in circumstances not listed above.

SYSTEMATIC WITHDRAWAL PLAN

This Plan is available if you wish to receive fixed payments from your investment in the Fund’s Common Stock in any amount at specified regular intervals. You may start a Systematic Withdrawal Plan if your shares of the Fund’s Common Stock have a market value of $5,000 or more. Shares must be held in your account as book credits. The Service Agent will act for you, make payments to you in specified amounts on either the 1st or 15th day of each month, as designated by you, and maintain your account.

Payments under the Systematic Withdrawal Plan will be made by selling exactly enough full and fractional shares of Common Stock to cover the amount of the designated withdrawal. Sales may be made on the New York Stock Exchange, to the agent or a trustee for one of the other Plans, or elsewhere. Payments from sales of shares will reduce the amount of capital at work and dividend earning ability, and ultimately may liquidate the investment. You can cancel the plan by giving the Fund 30 days notice in writing or by calling the Service Agent at (800) 345-6611, option 3. Sales of shares under this plan may result in gain or loss to you for income tax purposes. Withdrawals under this Plan or any similar withdrawal plan of any other investment company, concurrent with purchases of shares of the Common Stock or of shares of any other investment company, will ordinarily be disadvantageous to the Planholder because of the payment of duplicative commissions.

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LIMITATIONS ON PURCHASES AND SALES UNDER PLANS

Purchases and sales of shares of the Fund’s Common Stock through the foregoing plans (other than retirement plans) are limited to a total of 12,500 shares transacted per calendar quarter, subject to a maximum 40,000 shares per calendar year, per account (including any related accounts, e.g., those under the same social security number or tax identification number or otherwise under common control).

Additionally, the Fund’s stock repurchase program allows the Fund to repurchase up to 5% of the Fund’s outstanding Common Stock during the year directly from Stockholders and in the open market, provided that, with respect to shares purchased in the open market, the discount is greater than 10%. See “Prospectus Summary” for more information.

STOCKHOLDER INFORMATION

The Service Agent maintains books and records for all of the Plans, and confirms transactions to stockholders. To insure prompt delivery of checks, account statements and other information, you should notify the Service Agent immediately, in writing or over the phone, of any address changes. If you close your account, it is important that you notify the Service Agent of any subsequent address changes to ensure that you receive a year-end statement and tax information for that year. You will be sent reports quarterly regarding the Fund.

For information about your account held directly with the Fund you can write to Tri-Continental Corporation, P. O. Box 8099, Boston, MA 02266-8099 or the Service Agent may be telephoned Monday through Friday at (800) 345-6611, option 3 (within the United States) (except holidays) between the hours of 9:00 a.m. and 6:00 p.m. Eastern time. Your call will be answered by a service representative.

24-hour automated telephone access is available by dialing (800) 345-6611 (within the United States) on a touchtone telephone, which provides instant access to price, account balance, most recent transaction and other information. In addition, you may request Account Statements and Form 1099-DIV.

Issuance of Shares in Connection with Acquisitions

The Fund may issue shares of its Common Stock in exchange for the assets of another investment company in transactions in which the number of shares of Common Stock of the Fund to be delivered will be generally determined by dividing the current value of the seller’s assets by the current per share net asset value or market price on the New York Stock Exchange of the Common Stock of the Fund, or by an intermediate amount. In such acquisitions, the number of shares of the Fund’s Common Stock to be issued will not be determined on the basis of the market price of such Common Stock if such price is lower than its net asset value per share, except pursuant to an appropriate order of the Securities and Exchange Commission or approval by stockholders of the Fund, as required by law.

Some or all of the stock so issued may be sold from time to time by the recipients or their stockholders through brokers in ordinary transactions on stock exchanges at current market prices. The Fund has been advised that such sellers may be deemed to be underwriters as that term is defined in the 1933 Act.

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TABLE OF CONTENTS OF THE STATEMENT OF ADDITIONAL INFORMATION

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Additional information about the Fund and its investments is available in the Fund’s SAI, and annual and semiannual reports to stockholders. In the Fund’s annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund’s performance during its last fiscal year. The SAI is incorporated by reference in this prospectus. For a free copy of the SAI, the annual report or the semiannual report, contact the Fund directly or your financial intermediary. To make a stockholder inquiry, contact the financial intermediary through whom you purchased the Fund’s securities.

Tri-Continental Corporation

P.O. Box 8099

Boston, MA 02266-8099

Information is also available at columbiathreadneedle.com/us

Information about the Fund, including the SAI, can be viewed at the Securities and Exchange Commission’s (Commission) Public Reference Room in Washington, D.C. (for information about the public reference room call 1-202-551-8090). Reports and other information about the Fund are available on the EDGAR Database on the Commission’s Internet site at www.sec.gov. Copies of this information may be obtained, after paying a duplicating fee, by electronic request at the following E-mail address: publicinfo@sec.gov, or by writing to the Commission’s Public Reference Section, Washington, D.C. 20549-1520.

Investment Company Act File #811-00266

TICKER SYMBOL: TY

PRO240_12_E01_(05/15)

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STATEMENT OF ADDITIONAL INFORMATION

May 1, 2015

Tri-Continental Corporation

(the “Fund”)

225 Franklin Street
Boston, MA 02110

Toll-Free Telephone: (800) 345-6611, option 3

Unless the context indicates otherwise, references herein to “each Fund”, “the Funds”, “a Fund” or “Funds” refers to the Fund listed above.

This Statement of Additional Information (SAI) is not a prospectus, is not a substitute for reading any prospectus and is intended to be read in conjunction with the Fund’s current prospectus dated the same date as this SAI. The most recent annual report for the Fund, which includes the Fund’s audited financial statements for the period ended December 31, 2014, is incorporated by reference into this SAI.

Copies of the Fund's current prospectus and annual and semiannual reports may be obtained without charge by writing or calling the Fund at the Fund’s stockholder servicing agent, Columbia Management Investment Services Corp. (“CMISC” or the “Service Agent”) at P.O. Box 8099, Boston, Massachusetts 02266-8099 or at the telephone number above. The SAI, as well as the Fund’s most recent Annual and Semiannual Reports are also available at www.columbiathreadneedle.com/us.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission (“SEC”).