Custodial Brokerage Accounts

A custodial account lets an adult hold and manage investments for a minor who is too young to own a brokerage account outright. It is created under one of two state laws. UGMA, the older Uniform Gifts to Minors Act, covers mainly financial assets like cash, stocks, bonds, and funds. UTMA, the newer Uniform Transfers to Minors Act, is broader and can also hold assets like real estate. Most brokers open UTMA accounts today, and for a typical investor buying funds and stocks the two behave the same.

The core features are what make it distinct from a normal brokerage account.

• An adult manages it. The custodian, usually a parent, makes every investment decision until the child comes of age.
• The child owns the assets. The money legally belongs to the minor from the moment it goes in; the custodian is only managing it for them.
• Gifts are irrevocable. Once you contribute, you cannot take the money back or redirect it to another child.
• Control transfers at the age of majority. Depending on the state and how the account was set up, the child takes full control somewhere between 18 and 25.

Opening one is close to opening a regular brokerage account, with a few extra details because there are two people involved.

• Pick a broker that offers custodial accounts. Most major US brokers offer UTMA or UGMA accounts at no cost to open.
• Provide both sets of information. You enter your own details as the custodian and the child’s details, including their Social Security number, as the beneficial owner.
• Fund the account. Contributions are treated as gifts to the child. There is no contribution limit, though large gifts can have gift-tax reporting implications worth checking.
• Start investing. Once funded, you buy and manage investments inside the account just as you would in your own.

If you are still deciding which kind of account fits your goal, our overview of types of investment accounts lays out the options side by side.

A custodial account holds the same everyday investments as a standard brokerage account, which is a big part of its appeal. There are no special product restrictions beyond ordinary brokerage rules.

• Stocks and ETFs. Individual shares and low-cost index funds are the most common holdings for a long time horizon.
• Mutual funds and bonds. Broad funds and fixed income work the same as in any taxable account.
• Cash and cash equivalents. Money-market holdings and similar options are available while you decide how to invest.

Because a child often has decades before they need the money, many families lean toward broad, diversified, low-cost funds. That is an observation about time horizon, not a recommendation.

A custodial account is a taxable account, and the income is generally reported under the child’s Social Security number because they are the owner. The wrinkle is a set of rules known informally as the “kiddie tax,” designed to stop families from parking large amounts of investment income in a child’s name to be taxed at a lower rate.

• A first slice is tax-free. A set amount of the child’s unearned income each year is not taxed.
• The next slice is at the child’s rate. A further amount is taxed at the child’s usually low tax rate.
• Above the threshold, the kiddie tax applies. Unearned income beyond that point is taxed at the parent’s marginal rate, historically the trigger for the kiddie tax.

The exact dollar thresholds change every year, and the details can get involved. Treat this as a plain-language summary, not tax advice, and confirm current figures with the IRS or a tax professional before relying on them.

A custodial account trades some tax advantages and long-term control for flexibility and simplicity. Whether that tradeoff fits depends entirely on your goal for the money.

Pros

• Flexible use. The money can go toward anything that benefits the child, not just education.
• No contribution limit. You can gift as much as you like, subject to gift-tax reporting.
• Easy to open and run. It works like an ordinary brokerage account with a wide menu of investments.
• Some tax break for the child. The first slices of income are tax-free or taxed at the child’s low rate.

Cons

• The child gains full control. At the age of majority they can spend the money however they want.
• Fewer tax advantages. Unlike a 529 or a Roth, growth is not tax-free, and larger gains can hit the kiddie tax.
• Irrevocable gifts. You cannot reclaim the money or move it to another child.
• Financial-aid impact. Assets counted as the student’s can weigh more heavily in college aid formulas than a parent-owned account.

These three accounts all let you invest for a child, but they differ on who keeps control, how they are taxed, and what the money can be used for. The table below lines them up.

A 529 keeps the money earmarked for education with the owner in control and tax-free qualified withdrawals. A custodial Roth IRA is powerful for a child who has earned income, giving decades of tax-free growth toward retirement. A custodial UTMA account is the most flexible of the three because the money can be used for anything, at the cost of fewer tax breaks and an earlier handoff of control. Many families use more than one. This is educational, not a recommendation.

Trump Accounts are a newer tax-advantaged account for children, created under 2025 legislation, that includes government seed money for eligible newborns, annual contribution limits, and rules built around long-term saving. Compared with a custodial UTMA account, a Trump Account offers more built-in tax advantages and potential seed funding, while a custodial account offers more flexibility, no contribution cap, and a wider investment menu, in exchange for fewer tax breaks and the transfer of control at the age of majority.

If you are weighing them against each other, read our full Trump Accounts explainer for the eligibility, contribution, and withdrawal specifics. Both summaries here are informational and not advice; the rules are new and still settling, so verify current details before acting.

Walnut does not open custodial accounts or give tax advice, but it can help you think through how money invested for a child would be allocated. You can build a basket around a long-term thesis, set target weights, and see how it would have tracked against a benchmark, then place any trades yourself at your own broker. You connect your real broker, chat through Claude, ChatGPT, or built-in AI, and stay read-only until you choose to trade. For the account side of the decision, compare the types of investment accounts and talk to a tax professional. Walnut does not tell you what to buy.