Principal LifeTime Hybrid 2015 Fund - Class R5 (PHTRX) Exchange: NMFQS

The Fund operates as a “target date fund” that invests according to an asset allocation strategy designed for investors having a retirement investment goal close to the year in the Fund’s name. The Fund is a fund of funds that invests in underlying funds of Principal Funds, Inc. (“PFI”), with a majority of the Fund's assets invested in index funds. Its underlying funds consist of domestic and foreign equity funds, fixed-income funds, real asset funds, and other funds that aim to offer diversification beyond traditional equity and fixed-income securities. The asset class diversification of the Fund is designed to moderate overall price volatility. The Fund may add, remove, or substitute underlying funds at any time.The Fund is managed with strategic or long-term asset class targets and target ranges. There is a rebalancing strategy that aligns with the target weights to identify asset classes that are either overweight or underweight. The Fund may shift asset class targets in response to normal evaluative processes, the shortening time horizon of the Fund or changes in market forces or Fund circumstances.In selecting underlying funds and target weights, the Fund considers both quantitative measures (e.g., past performance, expected levels of risk and returns, expense levels, diversification and style consistency) and qualitative factors (e.g., organizational stability, investment experience, investment and risk management processes, and information, trading, and compliance systems). There are no minimum or maximum percentages of assets that the Fund must invest in a specific asset class or underlying fund. The underlying funds invest in growth and value stocks of small, medium and large market capitalization companies, fixed-income securities, domestic and foreign securities, securities denominated in foreign currencies, investment companies (including index funds), securitized products, U.S. government and U.S. government-sponsored securities, and derivatives. A derivative is a financial arrangement, the value of which is derived from, or based on, a traditional security, asset, or market index. The underlying funds principally use futures, options, swaps (including, for example, credit default, interest rate, and currency swaps) and forwards in order to gain exposure to a variety of securities or asset classes or attempt to reduce risk.The Fund's asset allocation will become more conservative over time as investment goals near (for example, retirement, which is assumed to begin at age 65) and investors become more risk-averse. Approximately 15 years after its target year, the Fund's underlying fund allocation is expected to match that of the Principal LifeTime Hybrid Income Fund. At that time, the Fund may be combined with the Principal LifeTime Hybrid Income Fund if the Board of Directors determines that the combination is in the best interests of Fund shareholders. It is expected that at the target date in the Fund’s name, the shareholder will begin gradually withdrawing the account's value.