Most states offering a 529 tax benefit cap the deductible amount per filer per year, so a large contribution doesn’t necessarily generate a proportionally larger state deduction.
How it works
The lesser of the contribution and the state’s per-filer deduction cap is the deductible amount; multiplying that by the state tax rate gives the state tax savings.
What this does not include
This does not include states with no income tax (where there’s no 529 deduction benefit at all), states offering a tax credit instead of a deduction, or rules that let married couples double the cap by contributing from separate accounts.
How to use this calculator
- Enter the contribution amount, your state’s deduction cap, and your state tax rate.
Frequently asked questions
Do I have to use my own state’s 529 plan to get the deduction?
It depends on the state — some states offer the deduction only for contributions to their own plan, while a handful offer it regardless of which state’s plan is used.
Can unused deduction room carry forward to future years?
Some states allow a multi-year carryforward for contributions exceeding the annual cap; others don’t — it varies significantly by state.
Does the federal government offer a 529 deduction too?
No — 529 contributions are never federally deductible; only some states offer an income tax deduction or credit at the state level.
