NORTHERN U.S.TREASURY INDEX FUND

U.S. TREASURY INDEX FUND

INVESTMENT OBJECTIVE

The Fund seeks to provide investment results approximating the performance of the Barclays U.S. Treasury Index.

FEES AND EXPENSES OF THE FUND

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees (USD $)	NORTHERN U.S.TREASURY INDEX FUND
Shareholder Fees (fees paid directly from your investment)	none

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

Annual Fund Operating Expenses		NORTHERN U.S.TREASURY INDEX FUND
Management Fees		0.30%
Other Expenses		0.38%
Administration Fees		0.15%
Transfer Agency Fees		0.10%
Other Operating Expenses		0.13%
Total Annual Fund Operating Expenses		0.68%
Expense Reimbursement	[1]	(0.53%)
Total Annual Fund Operating Expenses After Expense Reimbursement		0.15%

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. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	1 Year	3 Years	5 Years	10 Years
NORTHERN U.S.TREASURY INDEX FUND	15	164	326	796

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 portfolio operating expenses or in the Example, affect the Fund’s performance. During its most recent fiscal year ended November 30, 2012 and for the four-month period ended March 31, 2013, the Fund’s portfolio turnover rate was 74.49% and 21.88% (not annualized), respectively, 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 a representative sample of the U.S. Treasury obligations included in the Barclays U.S. Treasury Index. The Fund will buy and sell securities with the goal of achieving an overall duration and total return similar to that of the Barclays U.S. Treasury Index.

The Barclays U.S. Treasury Index is an unmanaged index that includes a broad range of U.S. Treasury obligations and is considered representative of U.S. Treasury bond performance overall. As of May 31, 2013, the duration of the Barclays U.S. Treasury Index was 5.25 years.

The Fund is passively managed, which means it tries to duplicate the investment composition and performance of the Barclays U.S. Treasury Index using computer programs and statistical procedures. Because the Fund will have fees and transaction expenses (while the Barclays U.S. Treasury Index has none), returns are likely to be below those of the Barclays U.S. Treasury Index.

The Fund's investment adviser expects that, under normal circumstances, the quarterly performance of the Fund, before expenses, will track the performance of the Barclays U.S. Treasury Index within a 0.95 correlation coefficient.

Barclays Capital, Inc. ("Barclays Capital") does not endorse any of the securities in the Barclays U.S. Treasury Index. It is not a sponsor of the Fund and is not affiliated with the Fund in any way.

PRINCIPAL RISKS

MARKET RISK is the risk that the market values of fixed-income securities owned by the Fund may decline, at times sharply and unpredictably.

MANAGEMENT RISK is the risk that a strategy used by the Fund's investment adviser may fail to produce the intended results.

LIQUIDITY RISK is the risk that certain portfolio securities may be less liquid than others, which may make them difficult or impossible to sell at the time and the price that the Fund would like, adversely affecting the value of the Fund's investments and its returns.

INTEREST RATE/MATURITY RISK is the risk that the value of the Fund's assets will decline because of rising interest rates. This risk is generally lower for funds that have shorter-weighted maturities, such as money market funds and short-term bond funds. The magnitude of this decline will often be greater for longer-term fixed-income securities than shorter-term fixed income securities.

PREPAYMENT (OR CALL) RISK is the risk that prepayment of the underlying mortgages or other collateral of some fixed-income securities may result in a decreased rate of return and a decline in value of those securities.

DEBT EXTENSION RISK is the risk that an issuer will exercise its right to pay principal on an obligation held by the Fund (such as a mortgage-backed security) later than expected. This may happen during a period of rising interest rates. Under these circumstances, the value of the obligation will decrease and the Fund will suffer from the inability to invest in higher yielding securities.

TRACKING RISK is the risk that the Fund's performance may vary substantially from the performance of the benchmark index it tracks as a result of share purchases and redemptions, transaction costs, expenses and other factors.

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. The Fund commenced operations on January 11, 1993 as a separate portfolio (the “Predecessor U.S. Treasury Index Fund”) of Northern Institutional Funds. On November 16, 2012, the Predecessor U.S. Treasury Index Fund was reorganized into the Fund (the “Reorganization”). Prior to the Reorganization, the Predecessor U.S. Treasury Index Fund offered and sold Class A shares. In connection with the Reorganization, holders of the Predecessor U.S. Treasury Index Fund’s Class A shares received shares of the Fund. The Predecessor U.S. Treasury Index Fund was managed with the same investment objective, strategies and policies as are followed by the Fund. As a result of the Reorganization, the performance and accounting history of the Predecessor U.S. Treasury Index Fund prior to the Reorganization were assumed by the Fund.

The performance information set forth in the bar chart and table below for periods prior to the Reorganization is that of the Class A shares of the Predecessor U.S. Treasury Index Fund.

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 Web site at www.northernfunds.com or by calling 800-595-9111.

CALENDAR YEAR TOTAL RETURN*

* Year to date total return for the six months ended June 30, 2013 is (2.17)%. For the periods shown in the bar chart above, the highest quarterly return was 8.80% in the fourth quarter of 2008, and the lowest quarterly return was (3.24)% in the second quarter of 2004.

AVERAGE ANNUAL TOTAL RETURN
(For the periods ended December 31, 2012)

Average Annual Total Returns	Inception Date	1-Year	5-Year	10-Year	Since Inception
NORTHERN U.S.TREASURY INDEX FUND	Jan. 11, 1993	1.71%	5.24%	4.58%	5.94%
NORTHERN U.S.TREASURY INDEX FUND Return after taxes on distributions		0.62%	3.95%	3.21%	4.03%
NORTHERN U.S.TREASURY INDEX FUND Return after taxes on distributions and sale of Fund shares		1.73%	3.87%	3.18%	3.97%
NORTHERN U.S.TREASURY INDEX FUND Barclays U.S. Treasury Index (reflects no deduction for fees, expenses, or taxes)		1.99%	5.40%	4.75%	6.14%

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-deferred 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 redemption are added to the redemption proceeds. Under certain circumstances, the addition of the tax benefits from capital 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.

[1] Northern Trust Investments, Inc. has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than acquired fund fees and expenses, a portion of the compensation paid to each Trustee who is not an officer, director or employee of Northern Trust Corporation or its subsidiaries, expenses related to third-party consultants engaged by the Board of Trustees of the Trust, membership dues paid to the Investment Company Institute and Mutual Fund Directors Forum, and extraordinary expenses and interest, if any) to the extent the "Total Annual Fund Operating Expenses" exceed 0.15%. This contractual limitation may not be terminated before July 31, 2014 without the approval of the Board of Trustees. Northern Trust Investments, Inc. serves as the investment adviser and administrator to the Fund. The Northern Trust Company, an affiliate of Northern Trust Investments, Inc., serves as transfer agent, custodian and sub-administrator to the Fund.