529 Plans: Why the Sticker Price Isn't What You'll Actually Pay

Last updated: September 2026 · Written by Hugo Cardozo

Today's tuition number isn't the planning target

College costs have historically climbed faster than general consumer inflation — commonly cited in the 4-6% annual range depending on the type of school. A savings plan built around today's sticker price, rather than a reasonably projected future price, is one of the most common and avoidable reasons 529 balances fall short, even when the account itself performs exactly as expected.

How a 529 balance actually grows

A 529 plan grows the same way any tax-advantaged investment account does: the existing balance compounds over time, and each new contribution adds its own growth on top from the moment it's deposited. The earlier and more consistently contributions are made, the more time each dollar has to compound before the child reaches college age — which is why starting early matters more in a 529 than almost any other savings goal with a fixed deadline.

Projecting the real cost, not today's cost

Take today's annual cost for the type of school you're planning around (public in-state, public out-of-state, or private all carry very different price tags) and grow it forward using a college-specific inflation assumption rather than general inflation — then multiply by the number of years of college. That inflated total, not today's number, is the real target to compare a projected 529 balance against.

What a projected gap actually means

Finding a shortfall years in advance is far more useful than discovering one at enrollment, because there's still time to act on it — raising the monthly contribution, even modestly, closes more of an early-identified gap than the same increase started later, purely because of how much compounding time remains. A gap also doesn't have to be closed by savings alone: financial aid, scholarships, work-study, and student loans commonly cover part of the cost for most families, and a 529 doesn't need to fund 100% of college to be worth having.

Why the assumptions deserve a range, not a single guess

Both the investment return and the college cost inflation rate are long-run estimates spanning many years, and small changes in either compound into a meaningfully different projected outcome. Running the numbers with a conservative case and an optimistic case, rather than trusting a single point estimate, gives a more honest sense of the range to actually plan around.

Frequently asked questions

What happens to 529 funds if my child gets a scholarship?

Funds up to the scholarship amount can typically be withdrawn without the usual 10% penalty on earnings (though the earnings portion still owes ordinary income tax), or the account can simply stay invested for graduate school, a different family member, or other qualified education expenses.

Can grandparents or other relatives contribute to a 529 plan?

Yes — most 529 plans accept contributions from anyone, and many plans now exclude grandparent-owned 529 distributions from counting against financial aid eligibility on the FAFSA under current rules, though it's worth confirming the specific plan and current guidance before relying on that.

Is it better to open one 529 per child or one shared account?

A separate account per child is generally simpler for tracking each child's own progress and target, though a single account can be reassigned to a different beneficiary if needed — the right structure often comes down to how many children you're saving for and how independently you want to track each goal.