COLUMBIA ADAPTIVE RETIREMENT 2020 FUND ADVISOR CLASS (CARGX) Exchange: NMFQS

Columbia Management Investment Advisers, LLC (the Investment Manager) manages the Fund using an adaptive risk allocation methodology. The Investment Manager employs quantitative and fundamental methods to identify distinct market states (capital preservation, neutral, bullish and highly bullish) and creates a strategic risk allocation to four broad asset categories (equity securities, fixed income securities issued by governments (rate assets), other fixed income securities (spread assets) and inflation-hedging assets) for each market state that is intended to generate attractive risk-adjusted returns in that market state. Allocations of risk to asset classes may differ significantly across market states. In addition to strategic risk allocations based on the market state, the Investment Manager may make tactical adjustments within and among asset classes and pursue opportunistic strategies in response to changing market, economic or other conditions. For these purposes, risk is the expected volatility (i.e., dispersion of returns) of a security, market, index or asset class, as determined by the Investment Manager.The Investment Manager allocates the Fund’s risk across global asset classes by reference to a specified “Target Date” (the year referenced in the name of the Fund), and periodically (generally monthly) reallocates risk across these asset classes as market or other conditions change, in an effort to provide capital appreciation and current income consistent with retirement as of the Target Date. As a general matter, the Fund’s overall risk allocation is determined by the Fund’s proximity to its Target Date, with an expectation that the further away the Target Date, the greater the Fund’s exposure to assets with greater expected risk, such as equities, that historically have tended to provide higher return potential relative to asset classes with historically less risk, such as fixed income securities. As time passes, and the Target Date nears, the expectation is that the Fund’s overall risk allocation will become more conservative. Fund risk allocations are managed up to and 25 years beyond the Target Date, and this gradual transition toward historically lower-risk assets over time is known as the “glide path.” Approximately 25 years past the Target Date (the Landing Point), the asset allocation for each market state will become static although the Investment Manager will continue to assess market states and adjust the Fund’s asset allocation in accordance with the glide path for the applicable market state and may make tactical allocation changes as well.The charts below show the Fund’s expected economic exposure (including leverage) to each of four broad asset categories. As the charts illustrate, the Fund’s economic exposure to the asset categories varies based on the current market state and proximity to the applicable Target Date. The Fund may utilize leverage within certain asset classes and during certain market states in order to maintain attractive expected risk-adjusted returns while adhering to the risk allocation framework. The charts also show that, for each market state, the Fund’s total economic exposure is expected to decline over time, although changes in the Investment Manager’s assessment of the market state may cause the Fund’s actual economic exposure to increase relative to its historical exposure at a time when the Investment Manager’s assessment of the market state was more conservative. The Investment Manager anticipates that the Fund’s net notional investment exposure will be approximately 115% of the net assets of the Fund in the neutral market state, although leverage may be higher (approximately 175% of net assets in the highly bullish market state) or lower in other market states or when the Investment Manager otherwise believes conditions so warrant. A Fund’s actual allocations may differ from the glide path when the Investment Manager makes tactical asset allocation changes. The Investment Manager intends to review the glide paths at least annually and may adjust the glide paths or change its asset categories or classes at any time. Neutral Glide Path   Bullish Glide Path   Capital Preservation Glide Path   Highly Bullish Glide Path   Although the Target Date is not intended to represent the retirement or other investment goal year of any specific investor, it is a factor in the construction of the glide path. The Investment Manager expects that most investors in the Fund plan to retire on or about the Target Date and that many investors will cease making new investments in the Fund and begin withdrawing from their accounts on or about the Target Date. The Board of Trustees of the Fund has the authority to combine the Fund with another Columbia Adaptive Retirement Fund once a Fund has reached its Landing Point, without obtaining shareholder approval.The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund.Investment in Underlying FundsUnder normal circumstances, the Fund will gain exposure to equity securities, rate assets, spread assets and inflation-hedging assets by investing in affiliated and unaffiliated funds (Underlying Funds). The glide paths shown above reflect the indirect exposure to the four asset categories gained through investment in the Underlying Funds.Under normal circumstances, the Investment Manager expects that approximately 80% of each Fund’s net assets will be invested in Columbia Solutions Aggressive Portfolio and Columbia Solutions Conservative Portfolio (the Solutions Series Funds), two mutual funds managed by the Investment Manager through which the Fund expects to gain the desired amount of leverage regarding each of the asset categories. As illustrated in the glide path below, each Fund’s investment in the Solution Series Funds will transition over time, with investments in Columbia Solutions Aggressive Portfolio continuing to decrease until approximately 25 years after the Target Date, the entire 80% of the Fund invested in the Solution Series Funds will be allocated to Columbia Solutions Conservative Portfolio. Under normal circumstances, Columbia Solutions Aggressive Portfolio will have more leverage and exposure to equity securities than Columbia Solutions Conservative Portfolio; in certain market states, these differences between these two Funds may be substantial.Under normal circumstances, the Investment Manager expects that approximately 20% of each Fund’s net assets will be invested in other mutual funds and ETFs. Currently, the Investment Manager intends to invest this portion of the Fund in Columbia Commodity Strategy Fund, a mutual fund managed by the Investment Manager, and third party ETFs. The Investment Manager can modify the list of Underlying Funds and types of instruments in which the Fund invests, or the asset categories, at any time, without the approval of or notice to Fund shareholders, including by adding Underlying Funds introduced after the date of this prospectus.Summary of the Principal Investment Strategies of the Solution Series FundsThe Solutions Series Funds (referred to together as the Fund) are non-diversified funds that pursue consistent total returns by seeking to allocate risks across multiple asset classes.Under normal circumstances, the Fund pursues its investment objective by allocating portfolio risk across multiple asset classes in U.S. and non-U.S. markets with the goal of generating consistent risk-adjusted returns. The Investment Manager employs the same methods described above for the Columbia Adaptive Retirement Funds to identify market states and create a strategic risk allocation for each state and to make tactical allocations.The Investment Manager may use a variety of security and instrument types to gain exposure to equity securities, inflation-hedging assets and fixed income securities. The equity securities in which the Fund may invest include direct or indirect investments in common stocks, preferred stocks and convertible securities. The inflation-hedging assets in which the Fund may invest include direct or indirect investments in inflation-linked bonds and real estate investment trusts. The fixed-income assets in which the Fund may invest include direct and indirect investments in corporate bonds, securities in the to-be-announced market, dollar rolls, exchange-traded notes (including both leveraged and inverse notes), sovereign debt obligations (including emerging market sovereign debt obligations), U.S. Government securities, repurchase agreements and reverse repurchase agreements. These securities or instruments may be issued by U.S. or non-U.S. entities (including issuers in emerging market countries) and they may have any maturity or credit rating. The Fund may also invest in currencies. Although the Fund may invest directly in these securities and instruments, it is expected that the Fund will primarily gain exposure to such securities and instruments through derivatives. The Investment Manager will determine, in its discretion, the categorization of any investment (or portion thereof) within one or more of the general asset class categories.The Fund may invest in derivatives, such as forward contracts, futures and swaps for both hedging and non-hedging purposes, including, for example, seeking to enhance returns or as a substitute for a position in an underlying asset. The Fund may invest in derivatives to manage the Fund's overall risk exposure. The Fund also expects to use derivatives to obtain leverage (market exposure in excess of the Fund’s assets). The Fund may utilize leverage within certain asset classes and during certain market states in order to maintain attractive expected risk-adjusted returns while adhering to the Fund's risk allocation framework. The Investment Manager anticipates that Columbia Solutions Aggressive Portfolio’s net notional investment exposure will be approximately 199% of the net assets of the Fund and approximately 80% of the portfolio invested in equities in the market state that the Investment Manager expects to be the most frequent, although leverage and the level of equity investment will vary in other market states or when the Investment Manager otherwise believes conditions warrant. The Investment Manager does not currently anticipate that Columbia Solutions Conservative Portfolio will be significantly leveraged and expects the portfolio to be invested approximately 20% in equities in the market state that the Investment Manager expects to be the most frequent.The Fund may also take short positions, for hedging or investment purposes.The Fund may invest in privately placed and other securities or instruments that are purchased and sold pursuant to Rule 144A or other exemptions under the Securities Act of 1933, as amended, subject to certain regulatory restrictions.The Fund may hold a significant amount of cash, money market instruments (which may include investments in one or more affiliated or unaffiliated money market funds or similar vehicles), other high-quality, short-term investments, or other liquid assets for investment purposes or to meet its segregation obligations as a result of its investments in derivatives. In certain market conditions, the Fund may have no market positions (i.e., the Fund may hold only cash and cash equivalents) when the Investment Manager believes it is in the best interests of the Fund.The Fund’s investment strategy may involve the frequent trading of portfolio securities.