Summary Prospectus by Investment Company (Form 497K)

SPECTRUM PREFERRED AND CAPITAL SECURITIES INCOME FUND

Class

A

C

J

Inst.

R-3

R-5

R-6

Ticker Symbol(s)

PPSAX

PRFCX

PPSJX

PPSIX

PNARX

PPARX

PPREX

Principal Funds, Inc. Summary Prospectus December 31, 2025

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 December 31, 2025, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus.

Objective

The Fund seeks to provide current income.

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 105 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 60 of the Fund's Statement of Additional Information.

If you purchase Institutional Class or Class R-6 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

R-6

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

3.75%

None

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

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			R-6
Management Fees			0.69%			0.69%			0.69%			0.69%			0.69%			0.69%			0.69%
Distribution and/or Service (12b-1) Fees			0.25%			1.00%			0.15%			N/A			0.25%			N/A			N/A
Other Expenses			0.10%			0.12%			0.15%			0.11%			0.33%			0.27%			0.01%
Acquired Fund Fees and Expenses			0.01%			0.01%			0.01%			0.01%			0.01%			0.01%			0.01%
Total Annual Fund Operating Expenses			1.05%			1.82%			1.00%			0.81%			1.28%			0.97%			0.71%

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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			$478			$697			$933			$1,609
Class C			285			573			985			1,935
Class J			202			318			552			1,225
Institutional Class			83			259			450			1,002
Class R-3			130			406			702			1,545
Class R-5			99			309			536			1,190
Class R-6			73			227			395			883

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			$185			$573			$985			$1,935
Class J			102			318			552			1,225

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 24.8% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets, plus any borrowing for investment purposes, in preferred securities and capital securities. Preferred securities typically include preferred stock and various types of junior subordinated debt and trust preferred securities. Preferred securities may pay fixed-rate or adjustable-rate distributions and generally have a payment "preference" over common stock, but are junior to the issuer's senior debt in a liquidation of the issuer's assets. Capital securities include Tier 2 subordinated debt securities issued by U.S. and non-U.S. financial institutions (including, but not limited to, banks and insurance companies), contingent convertible securities ("CoCos"), and certain preferred securities, issued by U.S. and non-U.S. corporations, financial institutions, and other issuers for purposes of satisfying regulatory capital requirements or obtaining rating agency credit. Capital securities may pay fixed-rate or adjustable-rate distributions and generally have a payment "preference" over common stock, but are junior to the issuer's senior debt in a liquidation of the issuer's assets. CoCos are hybrid debt securities typically issued by non-U.S. banking institutions that have contractual equity conversion or principal write-down features that are triggered by regulatory capital thresholds or regulatory actions calling into question the issuing banking institution's continued viability as a going-concern if the conversion trigger were not exercised.

Preferred securities purchased by the Fund are of companies with senior debt rated at the time of purchase BBB- or higher by S&P Global Ratings ("S&P Global") or Baa3 or higher by Moody's Investors Service, Inc. ("Moody's"). The Fund also invests up to 55% of its assets in below-investment-grade preferred securities and bonds (sometimes called "high yield bonds" or "junk bonds"), which are rated at the time of purchase Ba1 or lower by Moody's and BB+ or lower by S&P Global. 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 invests in other debt obligations, including (but not limited to) U.S. Treasury securities and obligations of the U.S. government, its agencies, and instrumentalities. The Fund invests in foreign securities. The Fund is not managed to a particular maturity or duration.

The Fund concentrates its investments (invests more than 25% of its net assets) in securities in one or more industries (i.e., banking, insurance, and commercial finance) within the financial services sector.

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The Fund also invests in derivative instruments, such as futures and options, for hedging and for income generation purposes. A derivative is a financial arrangement, the value of which is derived from, or based on, a traditional security, asset, or market index.

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.

Capital Securities Risk. In addition to the risks associated with other types of preferred securities and fixed-income securities, investing in capital securities includes the risk that the value of securities may decline in response to changes in legislation and regulations applicable to financial institutions and financial markets, increased competition, adverse changes in general or industry-specific economic conditions, or unfavorable interest rates.

Contingent Convertible Securities Risk. In addition to the general risks associated with fixed-income securities and convertible securities, the risks of investing in contingent convertible securities ("CoCos") include the risk that a CoCo may be written down, written off, or converted into an equity security when the issuer's capital ratio falls below a specified trigger level, or in a regulator's discretion depending on the regulator's judgment about the issuer's solvency prospects. Due to these features, CoCos may have substantially greater risk than other securities in times of financial stress. If the trigger level is breached, the issuer's decision to write down, write off, or convert a CoCo may result in the fund's complete loss on an investment in CoCos with no chance of recovery even if the issuer remains in existence.

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.

•Options. Options 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 options; counterparty risk; difference in trading hours for the options markets and the markets for the underlying securities (rate movements can take place in the underlying markets that cannot be reflected in the options markets); and an insufficient liquid secondary market for particular options.

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).

High Yield Securities Risk. High yield fixed-income securities (commonly referred to as "junk bonds") are subject to greater credit quality risk than higher rated fixed-income securities and should be considered speculative.

Industry Concentration Risk. A fund that concentrates investments in a particular industry or group of industries has greater exposure than other funds to market, economic, and other factors affecting that industry or group of industries.

•Financial Services. A fund concentrating in financial services companies may be more susceptible to adverse economic or regulatory occurrences affecting financial services companies. Financial companies may be adversely affected in certain market cycles, including periods of rising interest rates, which may restrict the availability and increase the cost of capital, and declining economic conditions, which may cause credit losses due to financial difficulties of borrowers. Because many types of financial companies are especially vulnerable to these economic cycles, the Fund's investments in these companies may lose significant value during such periods.

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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.

Preferred Securities Risk. Because preferred securities have a lower priority claim on assets or earnings than senior bonds and other debt instruments in a company's capital structure, they are subject to greater credit and liquidation risk than more senior debt instruments. In addition, preferred securities are subject to other risks, such as limited or no voting rights, deferring or skipping distributions, interest rate risk, and redeeming the security prior to any stated maturity date.

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.

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.

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.

For periods prior to the inception date of Class R-6 shares (January 3, 2017), the performance shown in the table for Class R-6 is that of the Fund's Institutional Class shares, adjusted to reflect the fees and expenses of Class R-6. However, where this adjustment for fees and expenses results in performance for Class R-6 that is higher than the historical performance of the Institutional Class shares, the historical performance of the Institutional Class shares is used. These adjustments result in performance for such periods that is no higher than the historical performance of the Institutional Class shares, which were first sold May 1, 2002.

Total Returns as of December 31

Highest return for a quarter during the period of the bar chart above:			Q2 2020			10.10%
Lowest return for a quarter during the period of the bar chart above:			Q1 2020			(12.31)%
Year-to-date return for Class A shares:			Q3 2025			6.49%

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Average Annual Total Returns

For the periods ended December 31, 2024

			1 Year			5 Years			10 Years
Class A Return Before Taxes			5.43%			1.53%			3.60%
Class A Return After Taxes on Distributions			3.97%			0.22%			2.14%
Class A Return After Taxes on Distributions and Sale of Fund Shares			3.87%			0.93%			2.44%
Class C Return Before Taxes			7.74%			1.54%			3.37%
Class J Return Before Taxes			8.65%			2.34%			4.00%
Institutional Class Return Before Taxes			9.81%			2.56%			4.27%
Class R-3 Return Before Taxes			9.25%			2.12%			3.78%
Class R-5 Return Before Taxes			9.70%			2.41%			4.09%
Class R-6 Return Before Taxes			9.81%			2.64%			4.31%
Bloomberg Global Aggregate Index (reflects no deduction for fees, expenses, or taxes)			(1.69)%			(1.96)%			0.15%
ICE BofA US All Capital Securities Index (reflects no deduction for fees, expenses, or taxes)			9.61%			2.57%			4.51%

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 Global Aggregate Index is the Fund's primary broad-based securities market index. The ICE BofA US All Capital Securities 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

Principal Global Investors, LLC

Sub-Advisor and Portfolio Managers

Spectrum Asset Management, Inc.

•Fernando ("Fred") Diaz (since 2010), Portfolio Manager

•Roberto Giangregorio (since 2010), Portfolio Manager

•L. Phillip Jacoby, IV (since 2002), Chief Investment Officer and Portfolio Manager

•Manu Krishnan (since 2010), Portfolio Manager

•Mark A. Lieb (since 2009), President and Chief Executive Officer

•Kevin Nugent (since 2014), Portfolio Manager

•Satomi Yarnell (since 2021), Portfolio Manager

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, R-5, and R-6			There are no minimum initial or subsequent investment requirements for eligible purchasers.			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.

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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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