529 or Brokerage Account? Two Ways to Start Investing for Your Kid

Every parent who opens an investing account for a child is making the same bet in two possible forms. Either they're betting the money will go to college — in which case a 529 plan hands them a meaningful tax advantage — or they're betting it might go to something else entirely, in which case that same tax advantage can turn into a penalty. The decision isn't really "which account is better." It's "how confident am I about what this money is for."

Here's the actual mechanics of both, without the sales pitch.

How a 529 plan actually works

A 529 plan is a state-sponsored, tax-advantaged account designed for education expenses. You contribute after-tax dollars — there's no federal deduction for putting money in — but the money grows tax-deferred, and withdrawals are entirely tax-free at the federal level as long as they're used for qualified education expenses: tuition, fees, room and board, books, and (thanks to changes from the One Big Beautiful Bill Act, effective for 2026) a meaningfully wider list than most parents assume.

Starting in tax year 2026, the annual cap on 529 withdrawals for K-12 tuition doubled from $10,000 to $20,000 per beneficiary. The same legislation expanded what counts as a qualified K-12 expense beyond tuition alone — curriculum materials, textbooks and digital learning tools, tutoring, and fees for standardized tests, AP exams, and dual-enrollment programs are now eligible. On the postsecondary side, 529 funds can now also cover programs leading to professional licenses, certifications, and technical credentials, including Department of Labor–registered apprenticeship programs. In plain terms: a 529 is no longer purely a "four-year university" account. It now flexes toward trade school, credentialing programs, and a broader slice of K-12 costs than it used to.

Most states also offer a state income tax deduction or credit for contributions to their own plan — the size and rules vary widely, so this is worth checking for your specific state before assuming it applies.

Non-qualified withdrawals get hit with income tax on the earnings portion plus a 10% federal penalty. There are exceptions — scholarships, death or disability of the beneficiary, and a newer option to roll a limited amount into a Roth IRA for the beneficiary under specific conditions — but the default assumption should be: this account is for education, full stop.

How a custodial brokerage account works

A custodial account — typically set up under the Uniform Transfers to Minors Act (UTMA) or the older Uniform Gifts to Minors Act (UGMA) — is a regular brokerage account that a parent or other adult manages on a child's behalf until they reach the age of majority in their state (usually 18 or 21). There's no tax break for contributing, and the account doesn't grow tax-free. Instead, it gets a modest tax advantage through what's informally called the "kiddie tax" structure: a portion of the child's unearned investment income is taxed at the child's own (typically lower) rate, with amounts above that threshold taxed at the parent's marginal rate.

The real feature of a custodial account isn't the tax treatment — it's the flexibility. The money can be invested in whatever the platform allows (stocks, ETFs, bonds) and spent on whatever benefits the child, not just education. A car, a gap year, a down payment, seed money for a business. There's no penalty for using it on something other than tuition, because nothing about the account assumes tuition in the first place.

The tradeoff is control. Once the child reaches the age of majority, the account — and everything in it — legally becomes theirs. A parent who spent fifteen years contributing doesn't get a vote in how an eighteen- or twenty-one-year-old spends it. That's a real consideration, not a hypothetical one.

The gifting math, if grandparents want to help

Both account types interact with the same gift tax rules, and this is where a 529 has one more edge worth knowing about: the "superfunding" election. In 2026, the annual gift tax exclusion is $19,000 per giver, per recipient ($38,000 for a married couple gift-splitting). Normally, gifts above that trigger the need to file a gift tax return, even if no actual tax is owed thanks to the lifetime exemption.

529 plans have a special carve-out: a donor can front-load five years' worth of annual exclusions into a single contribution — up to $95,000 from an individual, or $190,000 from a married couple — treating it as if it were spread evenly over five years for gift tax purposes. Custodial accounts don't get this election. If a grandparent wants to make one large lump-sum contribution toward college without any gift tax paperwork, a 529 is the only one of the two that accommodates it cleanly.

So which one should you actually open?

If you're highly confident the money is for education — your own household's college-savings culture, a state tax deduction that makes the math favorable, or you're already maxing out other tax-advantaged space — a 529 is hard to argue with. The tax-free growth on decades of compounding is real money, and the 2026 expansion of qualified expenses makes the "what if they don't go to a four-year school" objection weaker than it used to be.

If you want flexibility more than you want a tax break — or you're investing on behalf of a child for reasons that have nothing to do with tuition — a custodial brokerage account does that without penalty. Some families split the difference and fund both: a 529 for the education-specific savings, a smaller custodial account for everything else.

Neither account is a mistake. The mistake is picking one because it's what a friend used, without running your own numbers on your own state's tax treatment and your own certainty about how the money will eventually be spent.