Summary Prospectus by Investment Company (Form 497K)

SHORT-TERM INCOME FUND

Class

A

C

J

Inst.

R-3

R-5

Ticker Symbol(s)

SRHQX

STCCX

PSJIX

PSHIX

PSIOX

PSIQX

Principal Funds, Inc. Summary Prospectus March 1, 2026 as amended March 16, 2026

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus, Statement of Additional Information, Reports to Shareholders, and other information about the Fund online at www.PrincipalAM.com/Prospectuses. You can also get this information at no cost by calling 1-800-222-5852 or by sending an email request to [email protected].

The Fund's Prospectus and Statement of Additional Information, both dated March 1, 2026, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus.

Objective

The Fund seeks to provide as high a level of current income as is consistent with prudent investment management and stability of principal.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in Class A Shares of Principal Funds, Inc. More information about these and other discounts is available from your financial intermediary and in "Choosing a Share Class and The Costs of Investing" beginning on page 398 of the Fund's Prospectus, Appendix B to the Prospectus titled "Intermediary-Specific Sales Charge Waivers and Reductions," and "Multiple Class Structure" beginning on page 69 of the Fund's Statement of Additional Information.

If you purchase Institutional Class shares through certain programs offered by certain financial intermediaries, you may be required to pay a commission and/or other forms of compensation to the broker, or to your Financial Professional or other financial intermediary.

Shareholder Fees (fees paid directly from your investment)

Share Class

A

C

J

Inst.

R-3

R-5

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

2.25%

None

None

None

None

None

Maximum Deferred Sales Charge (Load) (as a percentage of the offering price or NAV when Sales Load is paid, whichever is less)

1.00%

1.00%

1.00%

None

None

None

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

			Share Class
			A			C			J			Inst.			R-3			R-5
Management Fees (1)			0.34%			0.34%			0.34%			0.34%			0.34%			0.34%
Distribution and/or Service (12b-1) Fees			0.15%			1.00%			0.15%			N/A			0.25%			N/A
Other Expenses			0.10%			0.19%			0.09%			0.04%			0.32%			0.26%
Acquired Fund Fees and Expenses			0.01%			0.01%			0.01%			0.01%			0.01%			0.01%
Total Annual Fund Operating Expenses			0.60%			1.54%			0.59%			0.39%			0.92%			0.61%

(1)Fees have been restated to reflect current fees.

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Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example assumes conversion of the Class C shares to Class A shares after the eighth year. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

			1 year			3 years			5 years			10 years
Class A			$285			$413			$552			$958
Class C			257			486			839			1,581
Class J			160			189			329			738
Institutional Class			40			125			219			493
Class R-3			94			293			509			1,131
Class R-5			62			195			340			762

With respect to Classes C and J shares, you would pay the following expenses if you did not redeem your shares (all other classes would be the same as in the above example):

			1 year			3 years			5 years			10 years
Class C			$157			$486			$839			$1,581
Class J			60			189			329			738

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 42.3% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to achieve its investment objective by investing in a broad range of high-quality, fixed-income securities. The Fund invests primarily in high-quality short-term bonds and other fixed-income securities that, at the time of purchase, are rated BBB- or higher by S&P Global Ratings ("S&P Global") or Baa3 or higher by Moody's Investors Service, Inc. ("Moody's"). If the security has been rated by only one of the rating agencies, that rating will determine the security's rating; if the security is rated differently by the rating agencies, the highest rating will be used; and if the security has not been rated by either of the rating agencies, those selecting such investments will determine the security's quality. The Fund's investments also include corporate securities, government securities, mortgage-backed and asset-backed securities (securitized products), and foreign securities.

Under normal circumstances, the Fund maintains an effective maturity of five years or less and an average portfolio duration that is within ±30% of the duration of the Bloomberg Credit 1-3 Year Index, which as of January 31, 2026 was 1.80 years.

The Fund invests in derivatives, including Treasury futures and credit index futures, for hedging purposes and to manage fixed-income exposure. A derivative is a financial arrangement, the value of which is derived from, or based on, a traditional security, asset, or market index.

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Principal Risks

The value of your investment in the Fund changes with the value of the Fund's investments. Many factors affect that value, and it is possible to lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The principal risks of investing in the Fund are listed below in alphabetical order and not in order of significance.

Derivatives Risk. Derivatives may not move in the direction anticipated by the portfolio manager. Transactions in derivatives may increase volatility, cause the liquidation of portfolio positions when not advantageous to do so, and result in disproportionate losses that may be substantially greater than a fund's initial investment.

•Futures. Futures contracts involve specific risks, including: the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract; possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; counterparty risk; and if the Fund has insufficient cash, it may have to sell securities from its portfolio to meet daily variation margin requirements.

Fixed-Income Securities Risk. Fixed-income securities are subject to interest rate, credit quality, and liquidity risks. The market value of fixed-income securities generally declines when interest rates rise, and increased interest rates may adversely affect the liquidity of certain fixed-income securities. Moreover, an issuer of fixed-income securities could default on its payment obligations due to increased interest rates or for other reasons.

Foreign Securities Risk. The risks of foreign securities include loss of value as a result of: political or economic instability; nationalization, expropriation, or confiscatory taxation; settlement delays; and limited government regulation (including less stringent reporting, accounting, and disclosure standards than are required of U.S. companies).

Portfolio Duration Risk. Portfolio duration is a measure of the expected life of a fixed-income security and its sensitivity to changes in interest rates. The longer a fund's average portfolio duration, the more sensitive the fund will be to changes in interest rates, which means funds with longer average portfolio durations may be more volatile than those with shorter durations.

Real Estate Securities Risk. Investing in real estate securities subjects the fund to the risks associated with the real estate market (which are similar to the risks associated with direct ownership in real estate), including declines in real estate values, loss due to casualty or condemnation, property taxes, interest rate changes, increased expenses, cash flow of underlying real estate assets, regulatory changes (including zoning, land use, and rents), and environmental problems, as well as to the risks related to the management skill and creditworthiness of the issuer.

Redemption and Large Transaction Risk. Ownership of the Fund's shares may be concentrated in one or a few large investors (such as funds of funds, institutional investors, and asset allocation programs) that may redeem or purchase shares in large quantities. These transactions may cause the Fund to sell securities to meet redemptions or to invest additional cash at times it would not otherwise do so, which may result in increased transaction costs, increased expenses, changes to expense ratios, and adverse effects to Fund performance. Such transactions may also accelerate the realization of taxable income if sales of portfolio securities result in gains. Moreover, reallocations by large shareholders among share classes of a fund may result in changes to the expense ratios of affected classes, which may increase the expenses paid by shareholders of the class that experienced the redemption.

Securitized Products Risk. Investments in securitized products are subject to risks similar to traditional fixed-income securities, such as credit, interest rate, liquidity, prepayment, extension, and default risk, as well as additional risks associated with the nature of the assets and the servicing of those assets. Unscheduled prepayments on securitized products may have to be reinvested at lower rates. A reduction in prepayments may increase the effective maturities of these securities, exposing them to the risk of decline in market value over time (extension risk).

U.S. Government Securities Risk. Yields available from U.S. government securities are generally lower than yields from many other fixed-income securities. The value of U.S. government securities may be adversely impacted by changes in interest rates, changes in the credit rating of the U.S. government, or a default by the U.S. government.

U.S. Government-Sponsored Securities Risk. Securities issued by U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and the Federal Home Loan Banks are not issued or guaranteed by the U.S. government.

Performance

The following information provides some indication of the risks of investing in the Fund. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You may get updated performance information at www.principalam.com/mutualfundperformance.

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The bar chart shows the investment returns of the Fund's Class A shares for each full calendar year of operations for 10 years (or, if shorter, the life of the Fund). These annual returns do not reflect sales charges on Class A shares; if they did, results would be lower. The table shows for the last one, five, and ten calendar year periods (or, if shorter, the life of the Fund), how the Fund's average annual total returns compare with those of one or more broad measures of market performance.

Total Returns as of December 31

Highest return for a quarter during the period of the bar chart above:			Q2 2020			3.37		%
Lowest return for a quarter during the period of the bar chart above:			Q1 2022			(2.48)		%

Average Annual Total Returns

For the periods ended December 31, 2025

			1 Year			5 Years			10 Years
Class A Return Before Taxes			2.89%			1.66%			2.16%
Class A Return After Taxes on Distributions			1.37%			0.60%			1.21%
Class A Return After Taxes on Distributions and Sale of Fund Shares			1.69%			0.81%			1.24%
Class C Return Before Taxes			3.31%			1.17%			1.64%
Class J Return Before Taxes			4.40%			2.16%			2.41%
Institutional Class Return Before Taxes			5.52%			2.35%			2.62%
Class R-3 Return Before Taxes			4.96%			1.81%			2.08%
Class R-5 Return Before Taxes			5.29%			2.13%			2.38%
Bloomberg US Aggregate Index (reflects no deduction for fees, expenses, or taxes)			7.30%			(0.36)%			2.01%
Bloomberg Credit 1-3 Year Index (reflects no deduction for fees, expenses, or taxes)			5.82%			2.46%			2.64%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only and would be different for the other share classes.

The Bloomberg US Aggregate Index is the Fund's primary broad-based securities market index. The Bloomberg Credit 1-3 Year Index is included as an additional index for the Fund as it shows how the Fund's performance compares with the returns of an index of funds with similar investment objectives.

Investment Advisor and Portfolio Managers

Principal Global Investors, LLC

•Jeff Callahan (since 2025), Portfolio Manager

•Michael Goosay (since 2023), Portfolio Manager

•Scott J. Peterson (since 2010), Portfolio Manager (delete on March 31, 2026)

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Purchase and Sale of Fund Shares

Share Class			Investment Type			Purchase Minimum Per Fund
A, C, and J			Initial Investment			$1,000(1)
A, C, and J			Initial Investment for accounts with an Automatic Investment Plan (AIP)			$100
A, C, and J			Subsequent Investments			$100(1)(2)
Institutional, R-3, and R-5			There are no minimum initial or subsequent investment requirements for eligible purchases.			N/A

(1)Some exceptions apply; see "Purchase of Fund Shares - Minimum Investments" for more information.

(2)For accounts with an AIP, the subsequent automatic investments must total $1,200 annually if the initial $1,000 minimum has not been met.

You may purchase or redeem shares on any business day (normally any day when the New York Stock Exchange is open for regular trading) through your plan, intermediary, or Financial Professional by sending a written request to Principal Funds at P.O. Box 219971, Kansas City, MO 64121-9971 (regular mail) or 801 Pennsylvania Ave., Ste. 219971, Kansas City, MO 64105-1307 (overnight mail); calling us at 1-800-222-5852; or accessing our website (www.principal.com).

Class C shares are subject to an 8-year automatic conversion plan whereby Class C shares held for eight years after purchase will automatically convert to Class A shares of the same Fund. See Purchase of Fund Shares for more information.

Tax Information

The Fund's distributions you receive are generally subject to federal income tax as ordinary income or capital gain and may also be subject to state and local taxes, unless you are tax-exempt or your account is tax-deferred in which case your distributions would be taxed when withdrawn from the tax-deferred account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment, or to recommend one share class of the Fund over another share class. Ask your salesperson or visit your financial intermediary's website for more information.

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