Money market funds produce ordinary income, taxed at your regular income tax rate

Money market funds hold short-term debt — Treasury bills, commercial paper, certificates of deposit — and pay you interest. That interest is ordinary income, meaning it gets added to your wages, self-employment income, and other earnings and taxed at whatever rate applies to your total income for the year. You report it on Form 1040, and the IRS taxes it the same way it taxes a paycheck.

The fund itself does not pay the tax. You do, when you file your return. The fund sends you a Form 1099-INT or Form 1099-DIV (depending on the fund type) showing how much interest you earned, and you report that figure to the IRS.

This is different from capital gains, which get special lower rates in many cases. Money market funds rarely produce capital gains because they hold bonds that mature quickly and stay close to par value. What you earn is interest — and interest is always ordinary income.

Key Takeaways

  • Interest from money market funds is taxed as ordinary income at your full marginal tax rate, not at capital gains rates.
  • The fund will send you Form 1099-INT or Form 1099-DIV showing the interest earned; you report this on your tax return.
  • If you hold the fund in a tax-deferred account like a 401(k) or traditional IRA, the interest is not taxed until you withdraw money.
  • State and local income tax also applies to money market fund interest unless the fund holds only Treasury securities.
  • You owe tax on the interest even if you reinvest it back into the fund rather than taking it as cash.

What form reports money market fund income

The fund company sends you Form 1099-INT if the fund holds mostly bonds and CDs, or Form 1099-DIV if it is structured as a dividend-paying fund. Both arrive by January 31 of the year after you earned the income. The form shows the total interest or dividends you received during the calendar year.

You receive one form per fund account. If you own money market funds at three different institutions, you get three forms. Add up all the 1099s you receive and report the total on your Form 1040, Schedule 1, line 1b (for interest income) or line 5a (for ordinary dividends).

Keep the forms with your tax records. The IRS receives a copy too, so the amount you report must match what the fund reported to the government.

How tax-deferred accounts change the picture

If you hold a money market fund inside a traditional IRA, 401(k), 403(b), or other tax-deferred retirement account, you do not report the interest on your current-year return. The interest compounds inside the account without triggering a tax bill each year.

When you withdraw money from the account — whether at retirement or earlier — that withdrawal is taxed as ordinary income. The entire amount you take out, including all the interest that accumulated, gets added to your income for that year and taxed at your rate then.

A Roth IRA works differently: you contribute after-tax dollars, the interest grows tax-free, and withdrawals in retirement are not taxed at all. Money market funds in a Roth produce no annual tax bill and no tax on withdrawal.

State and local tax on money market fund interest

Most states tax money market fund interest as ordinary income, just as the federal government does. Your state income tax rate applies to the interest you earn, in addition to federal tax.

The exception is interest from funds that hold only U.S. Treasury securities (Treasury bills, notes, and bonds). Federal law exempts Treasury interest from state and local income tax. Some money market funds market themselves as "Treasury-only" for this reason — the interest is still ordinary income for federal purposes, but you skip the state tax.

Check your state's tax rules if you live in a high-tax state like California, New York, or New Jersey. A Treasury money market fund may save you enough in state tax to justify a slightly lower yield.

Reinvested interest still counts as taxable income

Many money market funds let you automatically reinvest your interest — the fund pays you interest, and you when ready buy more shares of the same fund. This is convenient, but it does not reduce your tax bill.

You owe ordinary income tax on the interest the moment it is credited to your account, whether you take it as cash or reinvest it. The fund reports the full amount on your 1099, and you report it on your return. The fact that you did not withdraw the money does not matter.

This is a common source of confusion. A person might think "I did not touch the money, so I do not owe tax on it." That is not how the IRS works. You owe tax on income when you earn it, not when you spend it.

How much tax you actually pay depends on your total income

Money market fund interest gets added to all your other income — wages, self-employment income, capital gains, retirement distributions — and your total determines your tax bracket. The interest does not have its own separate rate.

If you earn $50,000 in wages and $2,000 in money market interest, your taxable income is $52,000. You pay tax on that $52,000 at whatever rate applies to someone earning $52,000 in your filing status and state. The $2,000 is taxed at your marginal rate — the rate that applies to your last dollar of income.

This matters because adding interest can push you into a higher bracket. If you are close to a bracket boundary, the interest might cost you more in tax than the interest itself is worth. This is rare with money market funds, which typically pay modest interest, but it is worth knowing.

Losses and expenses do not offset money market interest

You cannot deduct investment expenses to reduce the taxable interest from a money market fund. If the fund charges a management fee, you still report the full interest on your 1099 and pay tax on it. The fee comes out of your returns, but it does not reduce your taxable income.

If you sell shares of a money market fund at a loss, that loss does not offset the interest income. Capital losses can offset capital gains, but they cannot reduce ordinary income from interest. You report the interest and the loss separately on your return.

This is why money market funds held in taxable accounts are most useful for short-term cash reserves. The interest is fully taxable, and you get no deduction for costs. In a tax-deferred account, the interest compounds without annual tax bills, which is a much better outcome.

Frequently Asked Questions

Do I owe federal tax if I earned less than $1,000 in money market interest?

Yes. There is no minimum threshold for reporting interest income. If you earned any interest at all, you report it on your return. However, you may not owe any tax if your total income is below the standard deduction for your filing status — in that case, you have no tax liability even though you report the income.

What if the money market fund is in my child's name?

Your child reports the interest on their own return, or you report it on yours if they are a dependent and the amount is small. The "kiddie tax" rules may explore if your child is under 18 and has unearned income above a certain threshold — in that case, some of the interest may be taxed at your rate instead of theirs. Consult a tax professional for your specific situation.

Can I deduct money market fund losses against my ordinary income?

No. Capital losses from selling shares can offset capital gains, but not ordinary income like wages or interest. If you sell shares at a loss and have no capital gains to offset, you can deduct up to $3,000 of the loss against ordinary income in that year, with any excess carried forward to future years.

Is the interest taxed differently if the fund is at a bank versus a brokerage?

No. The source does not matter. Interest from a money market fund is ordinary income regardless of where you hold it. The fund sends you a 1099, and you report it the same way.

What if I earned interest but did not receive a 1099?

Contact the fund company. They are required to send a 1099-INT or 1099-DIV if you earned $10 or more in interest (the threshold varies slightly by form type). If you earned less, you still report the interest on your return, but the fund may not send a form. Keep your own records of all interest earned.