529 College Savings Calculator: Will You Have Enough

How the calculator works

The calculator has two sides: what you will have, and what college might cost. For the first, it grows your current 529 balance month by month at your chosen return and adds your monthly saving until the age college starts.

For the second, it takes the yearly cost you enter in today's dollars and raises it by your cost growth rate for each year until college starts, and for each year of college after that. Adding those years together gives the projected cost. The share covered is your balance divided by that cost. Finally, it works out the single monthly amount that, with your current balance, would grow to the full projected cost by the time college starts.

A worked example

Say your child is 2, college starts at 18, and the 529 already holds $5,000. You save $250 a month and assume a 5% return. You are planning for four years at $25,000 a year in today's dollars, with costs rising 3% a year.

After 16 years you have paid in $53,000 and the account is worth about $83,499. Meanwhile the four years of college, with costs rising for 16 to 19 years, are projected to cost about $167,837. Your savings would cover about 50% of that, leaving a gap of about $84,338. To cover it all, you would need to save about $540 a month instead of $250.

What changes the result

Starting early matters most. If the same child were 10 with the same $5,000 and $250 a month, the balance at 18 would be about $36,685 and would cover only 28% of a projected cost of $132,492. The monthly amount needed to cover it all jumps to about $1,068.

The return and the cost growth rate pull against each other. At a 6% return instead of 5%, the first example reaches about $91,815 and covers 55%. If you think costs will rise faster than your investments grow, the gap widens every year, so try a few combinations rather than relying on one.

For the yearly cost, use the published cost of attendance for the kind of school you have in mind.

529 plans and taxes

A 529 plan, which the IRS calls a qualified tuition program, is set up by a state or state agency, or by an eligible educational institution. Contributions are not deductible on your federal return. Withdrawals are not taxable when they pay for qualified higher education expenses, but if a withdrawal is more than those expenses, part of the earnings is taxable.

The Form 709 instructions treat contributions to a 529 for someone else as gifts to that person. For 2026, the first $19,000 of gifts to any one person is excluded from taxable gifts. If you put in more than that for one beneficiary, you can elect on Form 709 to treat the contribution as if it were spread evenly over five years. The IRS instructions for 2025 cap the election at $95,000, which is five times the $19,000 exclusion. The calculator warns you if your monthly saving adds up to more than $19,000 a year. Check your own plan's rules and any state tax treatment with the plan or a tax professional.

To see how the same monthly saving grows over different periods, use the compound interest calculator.