SPRXX yield: 3.64% as filed, and what it keeps after tax

What the filings say about SPRXX

Fidelity Money Market Fund is a prime fund: besides government paper it lends to banks and companies through commercial paper, certificates of deposit and repo backed by other collateral, which is how it earns more than a government fund. Its retail share class reported 3.64% for October 29, 2026, a little above SPAXX at 3.55%. Two things in the filings deserve attention. First, the fund is a retail prime fund under rule 2a-7, which means it keeps a stable $1.00 price only for individual investors and can charge a liquidity fee in stress. Second, its share of U.S. obligations moves a lot: 36.6% at the end of June, 14.1% at the end of September and 9% at the last month end. Below 50% at a quarter end, California, Connecticut and New York tax the whole dividend, so for residents of those states SPRXX gives up its yield edge and more.

SPRXX 7-day yield as filed, June 1, 2026 to October 29, 2026

A fund reports these yields once a month, within five business days of month end. Between two reports the figure here ages: by the time the October 2026 report is replaced, it is up to five weeks old. The fund’s own site shows today’s figure.

What SPRXX held on October 31, 2026

Share of the portfolio in U.S. government debt whose interest states cannot tax: 9.1%. This is the figure the calculator above uses as the state-tax-free part of the dividend. It is an estimate from the holdings on one day; the fund’s year-end tax statement gives the share of the year’s dividends, which is the figure for a tax return.

SPRXX and the 50% quarter-end test

In California, Connecticut and New York, the part of a dividend earned on U.S. government debt is state-tax-free only if the fund kept at least half its money in that debt at every quarter end. These quarter-end figures only decide pass or fail; the 9% above is the part the calculator treats as tax-free. SPRXX fell below half at one or more quarter ends in the data, so residents of the three states pay state tax on the whole dividend for the year. The law looks at the close of each quarter of the fund’s own tax year, which is not always the calendar quarter; calendar quarter-end reports are a close proxy, and the fund’s year-end letter says whether it qualified. How the rule works.

SPRXX at a glance

Where SPRXX ranks after tax

Among the 283 share classes in the data, for a single filer with $120,000 of taxable income and $50,000 in the fund:

The rank compares SPRXX with every other fund for a resident of that state. In a state with no income tax, such as Texas, funds whose dividends are taxed by states catch up, so the rank can be lower even though you keep more. In California, the fund ranked first kept $302 a year more than SPRXX on $50,000.

A rank of past yields, not a recommendation, and this site does not say which fund to hold. Moving cash to another fund can involve a minimum or a fee set by your brokerage. Rank every fund for your situation.

What to watch in SPRXX

The same portfolio is sold as FZDXX, a premium class with a $100,000 minimum that reported 3.76%. The expense drag of SPRXX on the filed figures was about 0.42%.