Three Different Rules Get Called "The 529 Rule"

Rule one: what counts as a qualified expense

Section 529(e)(3) is narrower than the phrase "college costs" suggests, and wider in two places people miss. Tuition, fees, books, supplies and equipment required for enrolment are in. Room and board are in only for a student enrolled at least half time, and only up to the institution's own room-and-board allowance in its published cost of attendance — or, if the student lives in housing owned or operated by the institution, up to the actual invoice. That ceiling matters: a student renting an expensive flat off campus cannot draw the rent tax-free above the school's published allowance. Computer equipment, software and internet access are in, if used primarily by the beneficiary while enrolled, but software designed for sports, games or hobbies is out unless it is predominantly educational. Transport is not a qualified expense, and neither is health insurance.

Three later paragraphs widen it. Section 529(c)(8) adds fees, books, supplies and equipment for a registered apprenticeship. Section 529(c)(9) adds repayment of qualified education loans, capped at 10,000 dollars lifetime per individual — with a separate 10,000 for each sibling, accounted against that sibling and not the beneficiary. And section 529(e)(3)(C), added in July 2025, brings in qualified postsecondary credentialing expenses, defined in a new subsection (f) covering recognised credential programmes. Each of these has its own effective date, and the newest ones apply to distributions made after 4 July 2025 — so a distribution taken in 2024 for the same purpose was not qualified even though the same purpose is qualified now.

Rule two: the K-12 limit is a different rule, and it moved

Until July 2025, the only elementary and secondary expense a 529 could pay was tuition. Section 70413 of the 2025 reconciliation act rewrote section 529(c)(7) to add curriculum and curricular materials, books and other instructional materials, online educational materials, tuition for tutoring or classes outside the home by an instructor who is not a relative and is either a licensed teacher, a former teacher at an eligible institution or a subject-matter expert, fees for nationally standardised norm-referenced achievement tests, advanced-placement examinations and college admission examinations, dual-enrolment fees, and educational therapies for students with disabilities provided by a licensed or accredited practitioner. That change applies to distributions made after the date of enactment, 4 July 2025.

The dollar cap is a separate provision with a separate effective date, and it doubled. The last sentence of section 529(e)(3)(A) limits aggregate cash distributions from all savings-type 529 programmes for one beneficiary in one taxable year to a fixed amount of K-12 expenses. Section 70413(b) raised that from 10,000 to 20,000 dollars, for taxable years beginning after 31 December 2025 — so 10,000 for 2025 and 20,000 from 2026. Two details are easy to miss. The cap is per beneficiary, not per account, so two grandparents with two accounts share one cap. And it applies to cash distributions, aggregated across programmes, which is why a family drawing from more than one plan has to add them up themselves.

Rule three: the state rule is a different rule

Nothing in section 529 gives a federal deduction for contributions. The deduction or credit that many savers actually receive is a state one, and states write their own rules: which plan qualifies for it, how much is deductible, whether a contribution to another state's plan counts, and — crucially — what a qualified distribution means for state purposes. States are free not to conform to the federal definition, and several do not conform on K-12 tuition or on student-loan repayment. The consequence is specific and unpleasant: a withdrawal that is entirely qualified federally can be non-qualified at state level, making the earnings taxable by the state and, in states with a deduction, triggering recapture of contributions you deducted in earlier years.

So before any withdrawal, answer three questions in order and in writing. Is the expense qualified under section 529(e)(3), including its room-and-board ceiling? If it is a K-12 expense, is it within the annual per-beneficiary cap, counting every plan the child has? And does your own state treat it the same way, including any recapture provision in its deduction? Only the third question needs a source outside the Internal Revenue Code, and it is the one people never look up.

What happens if the money is not needed

This is the objection that stops people opening an account, and the answer is less painful than the fear. A non-qualified withdrawal is not taxed in full: only the earnings portion is, pro rata to basis, and only that portion carries the additional 10 percent. On a 60,000-dollar balance built from 40,000 of contributions, a 10,000 withdrawal has an earnings portion of 3,333 dollars — so the penalty is 333 dollars and the income tax falls on 3,333, not on 10,000. There are also exceptions to the penalty, including a scholarship received by the beneficiary, up to the amount of the scholarship. And the beneficiary can be changed to another member of the family without tax.

There is one more route, and it has three conditions people repeat wrongly. Section 529(c)(3)(E) allows a direct trustee-to-trustee rollover from a 529 to a Roth IRA for the same beneficiary. The account must have been maintained for the fifteen-year period ending on the date of the distribution. The amount rolled over cannot exceed contributions made — and earnings on them — before the five-year period ending on that date, which rules out a last-minute top-up. Each year's rollover is capped at the beneficiary's own annual IRA contribution limit, reduced by any IRA contributions they made themselves that year, so it takes several years. And there is a lifetime aggregate ceiling of 35,000 dollars per beneficiary. It is a useful escape hatch, not an alternative retirement plan.

Contributions are gifts, and that has its own arithmetic

A contribution to a 529 is a completed gift to the beneficiary and not a future interest, which is why it uses the annual gift tax exclusion — 19,000 dollars for 2026 under Revenue Procedure 2025-32. Section 529(c)(2)(B) then adds something unusual: a donor whose contributions in one year exceed the annual exclusion may elect to spread the excess rateably over five years. That turns 95,000 dollars from one donor, or 190,000 from a couple electing to split, into five years of exclusions rather than a taxable gift — and it puts the whole sum to work eighteen years early rather than a fifth of it a year for five years.

The election has a cost worth naming: having used five years of exclusions on one beneficiary, the donor cannot make further excluded gifts to that person for the rest of the period without eating into the lifetime exclusion, and if the donor dies within the five years a portion is pulled back into the estate. It is a planning tool with consequences, not a trick — and it is one more reason the answer to "how much can I put in a 529?" is a set of interacting rules rather than a number.

Frequently asked questions

Did the K-12 limit really double?

Yes, and the date matters. The last sentence of section 529(e)(3)(A) caps the aggregate cash distributions from savings-type 529 programmes that can be applied to elementary and secondary expenses for one beneficiary in one taxable year. Section 70413(b) of the 2025 reconciliation act raised that figure from 10,000 to 20,000 dollars, effective for taxable years beginning after 31 December 2025 — so 10,000 for the 2025 tax year and 20,000 from 2026 onwards. A separate provision in the same section, with a different effective date, widened what counts as a K-12 expense beyond tuition to include curriculum materials, books, online materials, qualifying tutoring, standardised and admission test fees, dual-enrolment fees and educational therapies, for distributions made after 4 July 2025. And note the third rule: your state may not follow either change.

What actually happens if the child does not go to college?

Four things can happen, and only one of them is bad. You can change the beneficiary to another member of the family with no tax. You can leave the account open — there is no deadline. You can take a non-qualified withdrawal, on which only the earnings portion is taxed and carries the additional 10 percent, pro rata to basis: on a 60,000-dollar balance built from 40,000 of contributions, a 10,000 withdrawal has 3,333 dollars of earnings, so the extra tax is 333 dollars plus income tax on 3,333. Or, if the account has been open for fifteen years, you can roll amounts to the beneficiary's Roth IRA under section 529(c)(3)(E), subject to the five-year seasoning of contributions, the beneficiary's own annual IRA limit each year, and a lifetime cap of 35,000 dollars.

Can grandparents contribute, and how much at once?

Yes, and section 529(c)(2)(B) gives them an option nothing else has. A contribution is a completed gift to the beneficiary, so it uses the annual gift tax exclusion, which Revenue Procedure 2025-32 sets at 19,000 dollars for calendar year 2026. But a donor may elect to treat a contribution above the exclusion as made rateably over five years, which allows 95,000 dollars from one donor, or 190,000 from a married couple electing to split gifts, without a taxable gift. The trade-off is real: those five years of exclusions are used up for that beneficiary, and if the donor dies within the period a portion returns to the estate. Note also that the beneficiary's annual K-12 cap is per beneficiary, not per account — several accounts do not multiply it.

How much do I need to put in each month?

That depends entirely on the target you set, which is why the two calculators belong together. Take the projection from the college-cost article: a four-year public in-state budget eighteen years out at 4 percent cost inflation is 266,593 dollars at the published price and 183,579 at the average net price. At a 6 percent return over eighteen years, funding the published target needs 688 dollars a month and the net target needs 474. A contribution of 300 a month reaches 116,206, which is 44 percent of the published target and 63 percent of the net one. None of those four numbers is right or wrong; they are four different questions. Decide which target you are aiming at and what share of it savings should carry, then read the monthly figure off that.

Is the tax shelter worth more than picking a cheaper fund?

Compare them on the same scale and the answer stops being ideological. On 300 dollars a month for eighteen years, a 6 percent gross return produces 116,206. Losing 1.5 percentage points a year to tax drag inside a taxable account — say 4.5 percent net instead — produces 99,560, so the shelter is worth about 16,646 dollars under those assumptions. Now apply the same test to fees: 0.8 percent of annual charges turns the same 6 percent into 5.2 percent and produces 106,935, a cost of 9,271. Fees and tax are the same kind of leak measured on the same base, and the honest comparison is the net return after both. A tax-favoured plan with expensive funds can easily lose to a plain account with cheap ones; run both numbers rather than assuming.