Yes. Money market funds are taxed as ordinary income at the federal level, because the IRS treats their distributions as ordinary dividends rather than as interest or as qualified dividends. That means you pay tax at your marginal rate, which for tax year 2026 runs from 10% to 37%, no matter how long you have held the shares.1Internal Revenue Service. Publication 550 (2024), Investment Income and Expenses The rate you actually pay depends on your bracket, whether the fund holds government or municipal debt, and whether you own it in a taxable or retirement account.
Your Federal Rate Is Your Marginal Bracket
Ordinary dividends do not get the preferential rates that apply to qualified stock dividends or long-term capital gains. There is no holding-period discount. A dollar of money market fund income is taxed the same as a dollar of wages.1Internal Revenue Service. Publication 550 (2024), Investment Income and Expenses
For 2026, single-filer brackets are:
- 10% on taxable income up to $12,400
- 12% from $12,401 to $50,400
- 22% from $50,401 to $105,700
- 24% from $105,701 to $201,775
- 32% from $201,776 to $256,225
- 35% from $256,226 to $640,600
- 37% on income above $640,600
Married couples filing jointly use roughly doubled thresholds, with the top 37% rate starting above $768,700.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 So a shareholder in the 24% bracket owes 24 cents in federal tax on every dollar the fund distributes.
The 3.8% Net Investment Income Tax
Higher earners owe an extra 3.8% surtax on net investment income, which includes money market fund dividends. It applies to the smaller of your net investment income or the amount by which your modified adjusted gross income exceeds:
- $250,000 for joint filers
- $200,000 for single filers and heads of household
- $125,000 for married filing separately
The statute sweeps in gross income from interest, dividends, annuities, royalties, and rents.3Office of the Law Revision Counsel. 26 U.S. Code 1411 – Imposition of Tax For someone in the 37% bracket who also owes the surtax, the combined federal rate on money market fund income reaches 40.8%. Exempt-interest dividends from municipal funds are not counted in this calculation.4Internal Revenue Service. Questions and Answers on the Net Investment Income Tax
Treasury Funds and Your State Return
Federal law exempts interest on U.S. Treasury obligations from state and local income tax, and that exemption passes through to shareholders when a money market fund distributes dividends derived from Treasuries.5Office of the Law Revision Counsel. 31 U.S.C. 3124 – Exemption from Taxation You still owe federal ordinary income tax on the distribution. The state benefit can be significant if you live somewhere with a high income tax rate.
Fund companies publish a year-end statement showing what percentage of income came from qualifying federal obligations. Only that portion escapes state tax; income from corporate commercial paper, repurchase agreements, and other non-government holdings remains fully taxable at the state level. Some states also impose a minimum threshold, requiring the fund to hold a set percentage of its assets in government securities before allowing any pass-through exemption, so verify your state’s rule before claiming it.
Municipal Money Market Funds
Municipal money market funds hold short-term debt issued by state and local governments. Interest on those bonds is generally excluded from federal gross income, so the fund can pass tax-free dividends through to shareholders.6Office of the Law Revision Counsel. 26 U.S.C. 103 – Interest on State and Local Bonds The trade-off is a lower nominal yield than a comparable taxable fund.
Single-state municipal funds can create a double benefit for residents of the issuing state: the dividends avoid federal tax and the home-state income tax. That combination is most valuable in high-tax states.
The AMT Catch on Private Activity Bonds
Not every tax-exempt dividend stays exempt under the alternative minimum tax. Interest on certain private activity bonds, which finance projects with significant private business use, is a tax preference item for AMT purposes.7Office of the Law Revision Counsel. 26 U.S.C. 57 – Items of Tax Preference Bonds issued by 501(c)(3) organizations and certain housing bonds are excluded from the rule. Whether the AMT actually reaches you depends on the exemption for your filing status: for 2026, $90,100 for single filers (phasing out at $500,000) and $140,200 for joint filers (phasing out at $1,000,000).2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 Income below those amounts generally will not trigger AMT on private activity bond interest.
What Changes Inside a Retirement Account
The ordinary-income rules apply to money market funds held in a taxable brokerage account. Inside a tax-advantaged retirement account, the timing and character of the tax change.
In a traditional IRA or traditional 401(k), the dividends accumulate untaxed. You pay ordinary income tax when you take money out.8Internal Revenue Service. Traditional IRAs Deferral helps if your retirement bracket is lower than your working bracket, but the eventual withdrawal is still taxed at ordinary rates.
In a Roth IRA or Roth 401(k), qualified withdrawals (generally after age 59½ and at least five years after your first contribution) come out tax-free, so money market dividends earned inside the account may never be taxed.
Holding a municipal money market fund inside a retirement account rarely makes sense. The federal exemption on municipal interest is wasted when every dollar withdrawn from a traditional account will be taxed as ordinary income regardless of its source.
How the Income Shows Up at Tax Time
Your brokerage reports money market fund dividends on Form 1099-DIV, due to you by January 31.9Internal Revenue Service. General Instructions for Certain Information Returns (2025) Box 1a shows total ordinary dividends, including reinvested amounts.10Internal Revenue Service. Instructions for Form 1099-DIV For a municipal fund, exempt-interest dividends appear separately in Box 12. Those figures transfer to your federal return for the year the dividends were credited to your account.
Reinvested dividends are fully taxable in the year paid, even though you never touched the cash. If your fund automatically buys additional shares with each distribution, you still owe tax on the full 1099-DIV amount.11Internal Revenue Service. Stocks (Options, Splits, Traders) The IRS gets a copy of every 1099-DIV, and omitting one commonly triggers automated notices, underpayment penalties, and interest.12Internal Revenue Service. About Form 1099-DIV, Dividends and Distributions
When Estimated Payments Come Into Play
If your investment income is large enough that regular withholding will not cover the resulting tax, you may need quarterly estimated payments. The IRS generally requires them when you expect to owe at least $1,000 after withholding and refundable credits, and your withholding covers less than 90% of the current year’s tax or 100% of the prior year’s (110% if your AGI topped $150,000).13Internal Revenue Service. Estimated Tax Missing an installment can produce an underpayment penalty even if you pay the full balance when you file.