State tax quick wins

By Tom, CPA · Updated October 27, 2026

Part of: Easy Tax Strategies

TL;DR: State income tax is where many easy wins hide, because few people read the state return. Check whether your state gives a 529 deduction, subtract Treasury interest (it is exempt from state income tax), claim retirement income exclusions, take credits for tax paid to other states, get residency right when you move, and fix state withholding. Business owners should ask about a pass-through entity tax election.

Educational only, not tax, legal, or investment advice. Examples are illustrations, not predictions. Rules and limits change; verify current figures and talk to a qualified professional about your situation.

Most people treat the state return like the receipt at the bottom of the shopping bag: it exists, nobody reads it. Tax software fills it in from the federal numbers and moves on. That's a mistake, because states have their own deductions, exclusions and credits that the federal return never asks about, and software only finds them if you answer the extra questions.

Every state is different (and nine have no broad wage income tax at all), so this is a checklist of where to look. Rules are as of October 2026; check your state revenue department's site for current figures. For deeper planning, see state income tax planning.

CPA Warning Label: Moving to a no-tax state on paper while keeping your life in a high-tax state is how residency audits start. States look at where you actually live, not where your driver's license says.

1. Take the state 529 deduction

Many states give a deduction or credit for contributions to the state's own 529 plan, and a few allow it for any state's plan. Even if you'd use the money soon, contributing and then withdrawing for qualified expenses can capture the state break, subject to some states' holding rules. Federal rules now allow up to $20,000 a year of tax-free 529 withdrawals for K-12 tuition starting in 2026, but states don't all follow that. See 529 state deductions.

2. Subtract Treasury interest

Interest from U.S. Treasury bills, notes, bonds and savings bonds is exempt from state and local income tax (Publication 550). Software usually needs you to flag it, especially for Treasury money market funds, where only the share of income from Treasuries is exempt. The fund publishes that percentage each year.

Illustration

Morgan keeps $400,000 of cash in T-bills earning $16,000 of interest, and lives in a state with a 5% rate. Forgot the subtraction: $800 of state tax. Fixed: $0. If Morgan had held the same cash in a bank CD, all $16,000 would be state-taxable. Now multiply by the three prior years she can still amend: $2,400 of easy refunds, typically through amended state returns.

3. Claim retirement income exclusions

Many states exclude Social Security, part of pensions or IRA withdrawals, often with age or income limits. Some local taxes do too: Ohio municipal income taxes generally exempt Social Security, pensions and retirement benefit payments (Ohio Revised Code 718.01). Federal law bars states from taxing most retirement income of former residents who moved away (4 U.S.C. 114). See the state guides for Arizona, California and Colorado retirees.

4. Use the credit for taxes paid to other states

If you earn wages, rental income or business income in another state, you usually file there as a nonresident and claim a credit on your home-state return for tax paid. Skipping the credit means double taxation. Rentals in other states are a common example; see rental property state taxes.

5. Get residency right when you move

• File part-year returns in both states for the move year, splitting income by date.
• Change your driver's license, voter registration, car registration and mailing addresses.
• Keep records of days spent in each state if you keep a home in both.
• Time big income events, like selling a business or a large Roth conversion, for after you've truly moved to a lower-tax state.

6. Fix state withholding

Many states have their own withholding form. If you moved, work remotely in another state or retired, check that the right state is withholding. Retirees can often have state tax withheld from pensions and IRA withdrawals, which beats quarterly estimated payments.

7. Find state-only credits

Common examples: renter's or property tax credits (circuit breakers), earned income credits that piggyback on the federal EITC, child and dependent care credits, and credits for contributions to certain state programs. Michigan's homestead property tax credit is one example, capped at $1,900 for tax year 2025.

8. Business owners: ask about PTET

Most states with an income tax now allow partnerships and S corporations to elect to pay state tax at the entity level, which is deductible federally without hitting the SALT cap. It's valuable for owners above the SALT cap, but rules, deadlines and credits vary widely. Run the numbers with a preparer before electing.

A 20-minute state return review

Before you file this spring, open the state return PDF (not just the summary screen) and walk through it:

1. Starting point: most states start from federal AGI or taxable income. Confirm it matches the federal return.
2. Additions: look for items your state adds back, like out-of-state municipal bond interest or federal deductions your state doesn't allow. Make sure they're real.
3. Subtractions: this is where Treasury interest, retirement exclusions, 529 contributions and state-specific deductions live. If the list is empty, ask why.
4. Credits: other-state credits, family credits and property tax credits.
5. Payments: match state withholding to every W-2 and 1099-R, plus estimated payments.
6. Local returns: some cities, counties and school districts levy their own income taxes with separate filings.

Last year's state return is a great cheat sheet, because subtractions usually repeat.

9. Watch state conformity

States don't automatically follow federal law changes. Some decouple from bonus depreciation or other 2025 federal changes, so your state depreciation may differ from federal. Keep separate state depreciation schedules for rentals and business assets.

On the federal side, state income tax counts toward the SALT cap of $40,400 for most 2026 filers if you itemize. Back to easy tax strategies.