# EDGAR Filing Document

**Accession Number:** 0000916620
**File Stem:** 0001193125-25-169527
**Filing Date:** 2025-7
**Character Count:** 25699
**Document Hash:** a3686f70cb7fe75ffeb015ee8007268e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-169527.hdr.sgml**: 20250731

**ACCESSION NUMBER**: 0001193125-25-169527

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20250731

**DATE AS OF CHANGE**: 20250730

**EFFECTIVENESS DATE**: 20250731

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** NORTHERN FUNDS
- **CENTRAL INDEX KEY:** 0000916620

**ORGANIZATION NAME:**
- **EIN:** 391777365
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 0331

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-73404
- **FILM NUMBER:** 251168630

**BUSINESS ADDRESS:**
- **STREET 1:** NORTHERN FUNDS
- **STREET 2:** 50 SOUTH LASALLE STREET
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60603
- **BUSINESS PHONE:** 800-595-9111

**MAIL ADDRESS:**
- **STREET 1:** NORTHERN FUNDS
- **STREET 2:** 50 SOUTH LASALLE STREET
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60603

## Series and Classes Contracts Data

### SMALL CAP INDEX FUND (Series ID: S000001245)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000003391 | SMALL CAP INDEX FUND | NSIDX           |

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|:---|:---|
| **NORTHERN FUNDS**<br> **Small Cap Index Fund** | ![LOGO](g920229g36t24.jpg) |

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|:---|:---|
| **Summary Prospectus** \| **July 31, 2025** | **Shares Class:** NSIDX |

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&nbsp;&nbsp;&nbsp;Before you invest, you may want to review the Fund's complete Prospectus, which contains more information about the Fund and its risks. You can find the Fund's complete Prospectus, reports to shareholders, and other information about the Fund online at northerntrust.com/prospectus. You can also get this information at no cost by calling 800-595-9111 or by sending an e-mail request to northern-funds@ntrs.com. If you purchase shares of the Fund through a financial intermediary (such as a bank or a broker-dealer), the complete Prospectus and other information are also available from your financial intermediary. The Fund's complete Prospectus and Statement of Additional Information, both dated July 31, 2025, as supplemented, are incorporated by reference into this summary prospectus and may be obtained, free of charge, at the website, phone number or e-mail address noted above.

**INVESTMENT OBJECTIVE** 

The Fund seeks to provide investment results approximating the aggregate price and dividend performance of the securities included in the Russell 2000<sup>®</sup> Index (the "Index").

**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 be required to pay commissions and/or other forms of compensation to a financial intermediary for transactions in Shares Class shares, which are not reflected in the tables or the examples below.

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| | |
|:---|:---|
| **Shareholder Fees** (fees paid directly from your investment) | **Shareholder Fees** (fees paid directly from your investment) |
| **Annual Fund Operating Expenses** (expenses that you pay each year as a<br>percentage of the value of your investment) | **Annual Fund Operating Expenses** (expenses that you pay each year as a<br>percentage of the value of your investment) |
|  | **Shares<br>Class** |
|  Management Fees | 0.09% |
|  Other Expenses | 0.07% |
| &nbsp;&nbsp;&nbsp;&nbsp; Transfer Agent Fees | 0.04% |
| &nbsp;&nbsp;&nbsp;&nbsp; Other Operating Expenses | 0.03% |
|  **Total Annual Fund Operating Expenses** | 0.16% |
|  Expense Reimbursement<sup>(1)</sup> | (0.06)% |
|  **Total Annual Fund Operating Expenses After Expense Reimbursement<sup>(1)</sup>** | 0.10% |

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*<sup>(1)</sup>* *Northern Trust Investments, Inc. ("NTI") has contractually agreed to reimburse a portion of the operating expenses of the Fund so that after such reimbursement the Total Annual Fund Operating Expenses of the Fund (including acquired fund fees and expenses, but excluding extraordinary expenses) do not exceed 0.10%. NTI has also contractually agreed to reimburse the management fees payable by the Fund in an amount equal to the net management fee NTI earns on the amount invested by the Fund in money market funds managed by NTI. These contractual limitations may not be terminated before July 31, 2026 without the approval of the Board of Trustees.* 

**EXAMPLE** 

The following 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 also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
|  **Shares Class** | $11 | $46 | $85 | $199 |

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**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 20.51% of the average value of its portfolio.

**PRINCIPAL INVESTMENT STRATEGIES** 

Under normal circumstances, the Fund will invest substantially all (and at least 80%) of its net assets in the equity securities included in the Index, in weightings that approximate the relative composition of securities contained in the Index, and in Index futures approved by the Commodity Futures Trading Commission.

The Index measures the performance of the small-cap segment of the US equity universe. The Index is a subset of the Russell 3000<sup>®</sup> Index, which is designed to represent approximately 98% of the investable US equity market. It includes approximately 2,000 of the smallest securities in the Russell 3000<sup>®</sup> Index based on a combination of their market capitalization and current index membership, and represents approximately 5% of the total market capitalization of the Russell 3000<sup>®</sup> Index. As of May 31, 2025, the approximate median market capitalization of the companies in the Index was $840 million. The Index is rebalanced annually. The Fund generally rebalances its portfolio in accordance with the Index.

NTI uses a "passive" or indexing approach to try to achieve the Fund's investment objective. Unlike many investment companies, the Fund does not try to "beat" the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. NTI will buy and sell securities in response to changes in the Index as well as in response to subscriptions and redemptions. The Fund generally invests in substantially all of the securities in the Index in approximately the same proportions as the Index (i.e., replication). In certain circumstances, however, the Fund may not hold every security in the Index or in the same proportion as the Index, such as to improve tax efficiency or when it may not be practicable to

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|:---|:---|:---|
| NF SUM NSIDX (7/25) | SUMMARY PROSPECTUS<sub>1</sub> | SMALL CAP INDEX FUND |

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fully implement a replication strategy. Rather, it will use an optimization strategy to seek to construct a portfolio that minimizes tracking error versus the Index while managing transaction costs and realized capital gains and losses.

The Fund intends to be diversified in approximately the same proportion as the Index is diversified. The Fund may become "non-diversified," as defined in the Investment Company Act of 1940 (the "1940 Act"), solely as a result of a change in relative market capitalization or index weighting of one or more constituents of the Index. A "non-diversified" fund can invest a greater percentage of its assets in a small group of issuers or in any one issuer than a diversified fund can. Shareholder approval will not be sought if the Fund becomes non-diversified due solely to a change in the relative market capitalization or index weighting of one or more constituents of the Index.

In seeking to track the performance of the Index, from time to time the Fund may have a focused investment (i.e., investment exposure comprising more than 15% of its total assets) in one or more particular sectors. As of March 31, 2025, the Fund had focused investments in the health care, industrials and financials sectors.

NTI expects that, under normal circumstances, the quarterly performance of the Fund, before fees and expenses, will track the performance of the Index within a 0.95 correlation coefficient.

*The Index is created and sponsored by Frank Russell Company ("Russell"), as the index provider. Russell determines the composition and relative weightings of the securities in the Index and publishes information regarding the market value of the Index. Russell does not endorse any of the securities in the Index. It is not a sponsor of the Small Cap Index Fund and is not affiliated with the Fund in any way.* 

**PRINCIPAL RISKS** 

As with any investment, you could lose all or part of your investment in the Fund, and the Fund's performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund's net asset value ("NAV"), total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.

**MARKET RISK** is the risk that the value of the Fund's investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, elevated levels of government debt, changes in interest rates, lack of liquidity in the bond or equity markets or volatility in the equity markets. Market disruptions caused by local or regional events such as financial institution failures, changes in trade regulation or economic sanctions, internal unrest and discord, war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments. During periods of market disruption or other abnormal market conditions, the Fund's exposure to risks described elsewhere in this summary will likely increase.

**SMALL CAP STOCK RISK** is the risk that stocks of smaller companies may be more volatile than stocks of larger, more established companies, and may lack sufficient market liquidity. Small companies may have limited product lines or financial resources, may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally, the smaller the company size, the greater the risk.

**TRACKING RISK** is the risk that the Fund's performance may vary from the performance of the index it tracks as a result of share purchases and redemptions, transaction costs, expenses and other factors. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund's ability to adjust its exposure to required levels in order to track its Index or cause delays in the Index's rebalancing schedule. During any such delay, it is possible that the Index, and, in turn, the Fund will deviate from the Index's stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule.

**SECTOR RISK** is the risk that companies in similar businesses may be similarly affected by particular economic or market events, which may, in certain circumstances, cause the value of securities of all companies in a particular sector of the market to decrease.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;∎ **FINANCIALS SECTOR RISK** is the risk that companies
in the financials sector can be significantly affected by changes in interest rates, government regulation, the rate of corporate and consumer debt defaulted, price competition, and the availability and cost of capital, among other factors.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;∎ **INDUSTRIALS SECTOR RISK** is the risk that
companies in the industrials sector may be significantly affected by, among other things, worldwide economic growth, supply and demand for specific products and services, rapid technological developments, international political and economic
developments, environmental issues, and tax and governmental regulatory policies.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;∎ **HEALTH CARE SECTOR RISK** is the risk that
companies in the health care sector may be negatively affected by scientific or technological developments, research and development costs, increased competition within the health care sector impacting prices and demand for products or services,
rapid product obsolescence and patent expirations. The price of securities of health care companies may fluctuate widely due to changes in legislation or other government regulations, including uncertainty regarding health care reform and its
long-term impact, reductions in government funding and the unpredictability of winning government approvals.

**INDEX RISK** is the risk that that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Index, even if that security generally is

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|:---|:---|
| SMALL CAP INDEX FUND<sub>2</sub> | SUMMARY PROSPECTUS |

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underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of the Index. Additionally, the Fund rebalances its portfolio in accordance with the Index, and, therefore, any changes to the Index's rebalance schedule will result in corresponding changes to the Fund's rebalance schedule.

**DERIVATIVES RISK** is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;∎ **FUTURES CONTRACTS RISK** is the risk that there
will be imperfect correlation between the change in market value of the Fund's securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a
futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of the Fund's investment adviser to correctly predict the direction of securities'
prices, interest rates, currency exchange rates and other economic factors, which may make the Fund's returns more volatile or increase the risk of loss.

**NON-DIVERSIFICATION RISK** Under the 1940 Act, a fund designated as "diversified" must limit its holdings such that the securities of issuers which individually represent more than 5% of its total assets must in the aggregate represent less than 25% of its total assets. The Fund is "diversified" for purposes of the 1940 Act. However, in seeking to track its Index, the Fund may become "non-diversified," as defined in the 1940 Act, solely as a result of a change in relative market capitalization or index weighting of one or more constituents of the Index. A non-diversified fund can invest a greater portion of its assets in the obligations or securities of a small portion of its assets in the obligations or securities of a small number of issuers or any single issuer than a diversified fund can. In such circumstances, a change in the value of one or a few issuers' securities will therefore affect the value of the Fund more than if it was a diversified fund.

**SECURITIES LENDING RISK** is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral.

**As with any mutual fund, it is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank.** 

**FUND PERFORMANCE** 

The bar chart and table that follow provide an indication of the risks of investing in the Fund by showing (A) changes in the performance of the Fund from year to year, and (B) how the average annual total returns of the Fund compare to those of a broad-based securities market index and a style-specific index (one reflecting the market segments in which the Fund invests), in that order.

The Fund's past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future.

Updated performance information for the Fund is available and may be obtained on the Fund's website at northerntrust.com/funds or by calling 800-595-9111.

**CALENDAR YEAR TOTAL RETURN\***![LOGO](g920229g01a69.jpg)

*\* Year to date total return for the six months ended June 30, 2025 was (1.80)%. For the periods shown in the bar chart above, the highest quarterly return was 31.33% in the fourth quarter of 2020, and the lowest quarterly return was (30.72)% in the first quarter of 2020.* 

**AVERAGE ANNUAL TOTAL RETURN** 

*(For the periods ended December 31, 2024)* 

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| | | | |
|:---|:---|:---|:---|
|  | **1-Year** | **5-Year** | **10-Year** |
| &nbsp;&nbsp; Shares Class |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Returns before taxes | 11.48% | 7.25% | 7.66% |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Returns after taxes on distributions | 9.64% | 5.67% | 6.04% |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Returns after taxes on distributions and sale of Fund shares | 7.82% | 5.48% | 5.77% |
| &nbsp;&nbsp; Russell 3000<sup>®</sup> Index (reflects no deduction for fees, expenses, or taxes) | 23.81% | 13.86% | 12.55% |
| &nbsp;&nbsp; Russell 2000<sup>®</sup> Index (reflects no deduction for fees, expenses, or taxes) | 11.54% | 7.40% | 7.82% |

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*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. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.* 

*In calculating the federal income taxes due on redemptions, capital gains taxes resulting from redemptions are subtracted from the redemption proceeds and the tax benefits from capital losses resulting from the redemptions are added to the redemption proceeds. Under certain circumstances, the addition of the tax benefits from capital* 

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| SUMMARY PROSPECTUS<sub>3</sub> | SMALL CAP INDEX FUND |

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 *losses resulting from redemptions may cause the Returns after taxes on distributions and sale of Fund shares to be greater than the Returns after taxes on distributions or even the Returns before taxes.* 

**MANAGEMENT** 

**INVESTMENT ADVISER AND PORTFOLIO MANAGERS.** NTI, an indirect subsidiary of Northern Trust Corporation, serves as the investment adviser of the Small Cap Index Fund. Shivani Shah, Vice President of NTI, Chris J. Jaeger, Senior Vice President of NTI, Aaron Wang, Second Vice President of NTI, and Lucy A. Johnston, Vice President of NTI, have been managers of the Fund since December 2021, September 2024, July 2025, and September 2024, respectively. The Northern Trust Company, an affiliate of NTI, serves as transfer agent, custodian, securities lending agent, and sub-administrator to the Fund.

**PURCHASE AND SALE OF FUND SHARES** 

You may purchase Shares Class shares of the Fund by opening an account directly with Northern Funds (the "Trust") with a minimum initial investment of $2,500 in the Fund ($500 for an IRA; $250 under the Automatic Investment Plan; and $500 for employees of Northern Trust and its affiliates). The minimum subsequent investment is $50 (except for reinvestments of distributions for which there is no minimum). The Fund reserves the right to waive these minimums. You may also purchase Shares Class shares of the Fund through an account at Northern Trust (or an affiliate) or an authorized intermediary.

If you purchase, sell (redeem) or exchange Shares Class shares through an authorized intermediary, you may be required to pay a commission and/or other forms of compensation to the intermediary. In addition, an authorized intermediary may impose different investment minimums than those set forth above. The Fund is not responsible for any investment minimums imposed by authorized intermediaries or for notifying shareholders of any changes to them.

On any business day, you may sell (redeem) or exchange shares through your account by contacting your Northern Trust account representative or authorized intermediary. If you purchase shares directly from the Trust, you may sell (redeem) or exchange your shares in one of the following ways:

∎ By Mail – Send a written request to: Northern Funds, P.O. Box 75986, Chicago, Illinois 60675-5986.

∎ By Telephone – Authorize the telephone privilege on your New Account Application. Call 800-595-9111 to use
the telephone privilege.

∎ By Wire – Authorize wire redemptions on your New Account Application and have proceeds sent by federal wire
transfer to a previously designated bank account (the minimum redemption amount by this method is $250). You will be charged $15 for each wire redemption unless the designated bank account is maintained at Northern Trust or an affiliated bank. Call
800-595-9111 for instructions.

∎ By Systematic Withdrawal – If you own shares of the Fund with a minimum value of $10,000, you may elect to
have a fixed sum redeemed at regular intervals and distributed in cash or reinvested in one or more other funds of the Trust. Call 800-595-9111 for an application form and additional information. The minimum amount is $250 per withdrawal.

∎ By Exchange – Complete the Exchange Privilege section of your New Account Application to exchange shares of
one fund in the Trust for shares of another fund in the Trust. Shares being exchanged must have a value of at least $1,000 ($2,500 if a new account is being established by the exchange, $500 if the new account is an IRA). Call 800-595-9111 for more
information.

∎ By Internet – You may initiate transactions between Northern Trust banking and Fund accounts by using
Northern Trust Private Passport. For details and to sign up for this service, go to northerntrust.com/funds or contact your Relationship Manager.

**TAX INFORMATION** 

The Fund's distributions are generally taxable to you as ordinary income, qualified dividend income, capital gains, or a combination of the three, unless you are investing through a

tax-exempt or tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.

**PAYMENTS TO BROKERS-DEALERS AND OTHER FINANCIAL** I**NTERMEDIARIES** 

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. Ask your salesperson or visit your financial intermediary's website for more information.

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| SMALL CAP INDEX FUND<sub>4</sub> | SUMMARY PROSPECTUS |

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