For UTMA account tax reporting, the child is the taxpayer and the income is reported under the child’s Social Security number, but the federal Kiddie Tax rules mean any unearned income above $2,700 gets taxed at the parent’s marginal rate. The custodian handles the paperwork: collecting 1099s from the brokerage, tracking cost basis, and either filing a return for the child using Form 8615 or electing to fold the income onto the parent’s return with Form 8814. The right form depends on how much the account earned and what kind of income it produced.
Who Reports the Income
Every dollar in a UTMA belongs to the minor, and so does every dollar of income the account throws off. That means interest, dividends, and capital gains from securities sold inside the account are the child’s income, not the parent’s, and they get reported under the child’s Social Security number.
The most common setup mistake is opening the account with the parent’s SSN attached, or leaving it that way after a transfer. When the brokerage issues 1099s, they will go to whichever taxpayer ID is on file. If that’s the parent, the IRS will match the income against the parent’s return and eventually send a notice. Confirm with the financial institution that the child’s SSN is the taxpayer ID on the account before the first tax year closes.
The Kiddie Tax Brackets
The Kiddie Tax exists to keep parents from parking investment portfolios in a child’s name to soak up lower brackets. It applies to the child’s unearned income, which for a UTMA means interest, dividends, and gains from selling securities inside the account.
For 2025 and 2026, the structure has three tiers based on the child’s total unearned income:1Internal Revenue Service. Instructions for Form 8615 (2025)
- The first $1,350 is sheltered by the child’s standard deduction. No tax owed.
- The next $1,350 (income from $1,351 through $2,700) is taxed at the child’s own rate, usually 10%.
- Everything above $2,700 is taxed at the parent’s marginal rate, which can run as high as 37%.
The parent’s rate applies whether the income lands on the child’s separate return or on the parent’s return.
Which Children the Rules Cover
The Kiddie Tax reaches further than most parents assume. It applies if at least one parent is alive at year-end, the child does not file a joint return, and the child falls into one of these categories: under 18 at year-end; age 18 with earned income of half or less of their own support; or a full-time student aged 19 through 23 with earned income of half or less of their support.2Office of the Law Revision Counsel. 26 U.S. Code 1 – Tax Imposed
The support test is where college-age children get pulled back in. A student with a summer job that covers only a slice of tuition and living costs is still subject to the Kiddie Tax on UTMA dividends. Once earned income exceeds half of support, or the student ages out, the account’s income is taxed entirely at the child’s own rate going forward.
Choosing Between Form 8615 and Form 8814
When a UTMA generates enough income to file, there are two ways to handle it.
Form 8615: A Separate Return for the Child
A separate Form 1040 in the child’s name is required any time gross unearned income exceeds $1,350, the dependent’s standard deduction amount.3Internal Revenue Service. Publication 501 (2025), Dependents, Standard Deduction, and Filing Information If unearned income also exceeds $2,700, Form 8615 (Tax for Certain Children Who Have Unearned Income) attaches to that return and calculates how much of the income gets taxed at the parent’s rate.1Internal Revenue Service. Instructions for Form 8615 (2025)
Form 8615 accepts any mix of income types, including capital gains from selling individual stocks or fund shares. It’s the only option if income exceeds the Form 8814 ceiling or if estimated payments were made for the child during the year.
Form 8814: Reporting the Child’s Income on Your Own Return
Form 8814 (Parents’ Election to Report Child’s Interest and Dividends) lets you fold the account’s income directly onto your Form 1040, skipping a separate return for the child. The child has to meet every one of these conditions:
- Only interest, dividends, and capital gain distributions (the automatic payouts from mutual funds), with no other income.
- Gross income under $13,500 for 2025.
- No estimated tax payments made for the child during the year.
Capital gain distributions from mutual funds qualify. Gains from actually selling individual securities do not.4Internal Revenue Service. Instructions for Form 8814 (2025) If the custodian sold any stock, ETF shares, or bonds inside the UTMA during the year, Form 8814 is off the table.
The Hidden Cost of Electing Form 8814
Form 8814 is simpler on paper, but it can cost more in tax. Under the election, the child’s income between $1,350 and $2,700 is taxed at a flat 10%. On a separate return, qualified dividends and capital gain distributions in that same band can qualify for the 0% long-term capital gains rate. The IRS estimates the difference at up to $135 per year.5Internal Revenue Service. 2025 Instructions for Form 8814 For a UTMA holding mostly index funds that throw off qualified dividends, the separate return often wins even with the extra paperwork.
The 1099s You’ll Receive and Why Basis Matters
Each year, the brokerage sends the custodian a set of forms that feed into the child’s return (or into Form 8814 on yours):
- Form 1099-INT for interest from bonds, CDs, or money market holdings.
- Form 1099-DIV for dividends and capital gain distributions from mutual funds or ETFs.
- Form 1099-B for proceeds from sales, and in most cases the cost basis of what was sold.
Basis tracking is where careless recordkeeping gets expensive. Cost basis is the purchase price plus any reinvested dividends and commissions. When a position sells, only the gain over that basis is taxable. Lose the basis records and the sale can look like pure gain, inflating the tax bill. Accounts that have been reinvesting dividends for a decade are especially vulnerable, because each reinvestment added to basis and none of it should be taxed twice.
Even in years the account earns too little to trigger a filing, hold onto the 1099s. They matter when the child eventually sells positions in adulthood and needs to reconstruct what was paid for what.
Estimated Payments and Late-Filing Penalties
UTMA income has no withholding. If the account throws off enough to owe meaningful tax, the safe move is quarterly estimated payments under the child’s SSN. The safe harbor for avoiding an underpayment penalty is paying at least 90% of the current year’s tax or 100% of the prior year’s tax through estimates.6Internal Revenue Service. Topic No. 306, Penalty for Underpayment of Estimated Tax
Miss the filing deadline and the usual penalties apply. The failure-to-file penalty is 5% of the unpaid tax per month (or part of a month), capped at 25%. Once a return runs more than 60 days late, the minimum penalty is the lesser of $525 or 100% of the unpaid tax.7Internal Revenue Service. Failure to File Penalty A separate 0.5% per month failure-to-pay penalty runs alongside it for the first five months, and interest accrues on the whole balance from the original due date.
Reporting the Handoff at the Age of Majority
A UTMA ends when the child hits the age of majority set by state law, generally 21 for gift-funded accounts, though some states use 18 and a few let the donor specify an age up to 25. When the assets move to a regular brokerage account in the now-adult’s name, the transfer itself isn’t a taxable event. No gain is triggered, and the cost basis of each position carries over.
Income earned in the account before the transfer date still gets reported under the Kiddie Tax rules for that final year. After the transfer, the adult reports everything on their own return at their own rate. Hand over clean basis records with the account. Without them, every future sale risks overstating gain.
A Note on Contributions
Reporting the account’s annual income is one side of the ledger. On the contribution side, funding a UTMA is an irrevocable gift by the donor, and gifts above the annual exclusion ($19,000 per recipient in 2026) require the donor to file Form 709.8Internal Revenue Service. What’s New — Estate and Gift Tax That filing sits on the donor’s tax return, not the child’s, and doesn’t affect how the account’s income gets reported.