529 State Tax Deduction Calculator (2026)

The 529 deduction is a subtraction from your state taxable income for the year you make the contribution. If your state's top rate is 5.75% and you contribute $10,000 to a qualifying 529, the deduction reduces your state taxable income by up to your state's cap and saves you the cap times your marginal rate. Some states cap the deduction at a flat dollar figure ($5,000 in New York, $10,000 in Illinois); a few (Colorado, New Mexico, South Carolina, West Virginia) let you deduct the full contribution. A handful (Indiana, Utah, Vermont, Oregon, Minnesota) run a tax credit instead of a deduction, which is often more valuable at the same contribution level. Credits reduce your tax dollar for dollar; deductions only reduce it by your marginal rate.

Most states require you to contribute to their own plan to claim the deduction ("in-state only"). A minority (Arizona, Arkansas, Kansas, Maine, Minnesota, Missouri, Montana, Ohio, Pennsylvania) let residents deduct contributions to any state's 529 plan. Pennsylvania is the most generous of these: full deduction up to the federal gift-tax annual exclusion ($19,000 in 2026) per beneficiary, into any state's plan.

The amount above the cap is not deductible in the year you contribute it, but the money still grows federal-tax-free inside the 529 and is still eligible for tax-free qualified withdrawals. A few states offer a carryforward: Connecticut lets you carry deductions forward five years; Maryland ten years; Virginia and Ohio have unlimited carryforward. So even large one-off contributions can be spread across future tax returns to capture the deduction. Check your state's specific carryforward rule before superfunding a 529.

Usually yes, for the same annual contribution. A 20% credit on $7,500 (Indiana) gives $1,500 back regardless of your marginal rate. A deduction of $10,000 in Illinois only saves $495 (10,000 × 4.95%). Indiana's $1,500 credit is the single largest state benefit in the country. Utah, Vermont, and Oregon have smaller caps but the credit mechanism still delivers a higher dollar return than a comparable deduction. Minnesota is unique: it lets you choose a credit or a subtraction, so run both numbers.

Generally it applies to the taxpayer who made the contribution, not the account owner. That means grandparents in states with an any-plan deduction (Pennsylvania is the widest example) can capture their own state deduction even when the 529 is owned by the parents in a different state. In-state-only states usually require the contributor to be a resident. Check the specific plan administrator's language before assuming a grandparent contribution earns anyone a state deduction.

For a deduction state, it equals your marginal state rate. New York at $10,000 joint = 6.85% x $10,000 = $685. Indiana's credit at $7,500 = $1,500 = 20% of the contribution. Unlimited-deduction states (Colorado 4.4%, New Mexico 5.9%, South Carolina 5.21%, West Virginia 4.58%) return their top rate on every dollar you put in. This is why the deduction is best thought of as a matching contribution from the state, not a rebate.