Custodial Accounts and the Kiddie Tax

A custodial account looks like a flexible alternative to a 529 until you read two things: who legally owns it, and how its income gets taxed.

Last verified 2026-07-25

The transfer is irrevocable, and that's the point

A custodial account under the Uniform Transfers to Minors Act or Uniform Gifts to Minors Act is a gift to the child. Legally the assets are theirs from the moment of transfer; you are the custodian, not the owner.

You can't take it back, redirect it to a sibling, or restrict what it's spent on. At the age of majority — which varies by state, commonly 18 or 21 — the account transfers to their control outright, to use for anything at all.

That's the sharpest contrast with a 529, where the account owner keeps control and can change the beneficiary. Custodial accounts buy flexibility of use and give up control entirely.

The kiddie tax, in three tiers

The kiddie tax exists to stop families shifting investment income to a child in a lower bracket. It applies to a child's unearned income — interest, dividends, capital gains — not to money they earn from work.

It works in tiers, and the thresholds are inflation-adjusted each year. A first slice of unearned income is untaxed. A second, equal-sized slice is taxed at the child's own rate. Everything above that is taxed at the parents' rate.

So the strategy the account appears to enable is capped by design. The exact thresholds change annually — check the current Rev. Proc. rather than relying on a figure from any summary, including this one.

The financial aid consequence

Assets owned by the student are generally assessed more heavily in financial aid formulas than assets owned by a parent.

Because custodial assets legally belong to the child, they're counted as the student's. A 529 owned by a parent is generally treated as a parental asset, which is assessed at a lower rate.

This is a structural difference worth knowing before choosing a vehicle, not a reason to avoid custodial accounts outright. This is education about how the accounts differ, not advice on which to use — that depends on circumstances no lesson can see.