State tax filing: file state taxes online and handle your state income tax return in any state

Which states have no income tax, and which have a flat rate

Eight states levy no individual income tax at all. Washington is usually mentioned in the same breath, but it belongs in its own row: it taxes capital gains income only, and leaves wages alone. That is why you will see the figure quoted as either eight states or nine, depending on whether the writer counts Washington.

The New Hampshire line is the one that trips people up. Plenty of articles still list it as taxing investment income, because it did until the interest and dividends tax was repealed as of 2025. For a tax year 2025 return there is nothing to file there.

Among the states that do tax income, the split is between flat and graduated rates. As of January 1, 2026, fifteen states use a single flat rate: Arizona, Colorado, Georgia, Idaho, Illinois, Indiana, Kentucky, Louisiana, Michigan, Mississippi, Missouri, Nebraska, North Carolina, Ohio, and Pennsylvania. For a tax year 2025 return the count was fourteen, because Ohio's 2.75 percent flat rate and Georgia's 5.19 percent flat rate both took effect on January 1, 2026. If you are filing a 2025 return for either state, you are still working under the old graduated schedule.

The other 26 states plus DC use graduated brackets. Bracket counts run from two (Arkansas, Kansas, Massachusetts, Montana, North Dakota) up to twelve in Hawaii, the most of any state. Several of the biggest states have their own dedicated pages here: California tax filing, New York state tax filing, New Jersey tax filing, Illinois tax filing, Pennsylvania tax filing, Massachusetts tax filing, Virginia tax filing, Georgia tax filing, Maryland tax filing, Minnesota tax filing, and Wisconsin tax filing, Connecticut tax filing, South Carolina tax filing, Missouri tax filing, Oregon tax filing, and Alabama tax filing. Among the flat-rate states, we also have dedicated guides for Ohio tax filing, North Carolina tax filing, Michigan tax filing, Arizona tax filing, Colorado tax filing, Indiana tax filing, and Kentucky tax filing.

State tax filing deadlines for 2026

Most states simply adopt the federal date, which for tax year 2025 returns was April 15, 2026. A handful set their own, and those are the ones that catch people who assume one deadline covers everything.

State extension rules diverge even more than the deadlines do, and assuming they work like the federal extension is an expensive habit. California grants an automatic six-month extension to file with no form and no application at all, moving the date to October 15, 2026. New York grants the same six months but requires you to actually file Form IT-370 by April 15 to get it, along with payment for anything you owe.

What almost every state copies from the IRS is the important part: an extension moves the filing date, not the payment date. Whatever you owe is still due in April, and interest starts running from there. Our guide to filing a tax extension covers how that works federally, and the full 2026 deadline calendar lays out every date in one table.

Filing in more than one state

Multi-state filing is where self-prepared returns go wrong most often, and it is more common than people expect: a remote job across a state line, a move in July, a few months of contract work somewhere else. The general pattern is straightforward once you see it.

• Resident return in the state you live in, reporting all of your income wherever it was earned. Your home state normally gives you a credit for tax paid to other states so the same dollars are not taxed twice.
• Nonresident return in any state where you earned income but did not live, reporting only the income sourced to that state.
• Part-year resident returns in each state if you moved during the year, splitting your income by the dates you lived in each one.

Most states fold the nonresident and part-year cases into a single combined form. California uses Form 540NR for both; New York uses Form IT-203. The thresholds for when a nonresident has to file are less forgiving than people assume. As of January 1, 2026, 22 states set no meaningful nonresident filing threshold at all, so essentially any income sourced there creates a filing requirement. Nine states use an income-based threshold, ranging from \$100 in Vermont up to \$15,300 in Minnesota. Connecticut and Maine use a combination of day counts and income.

The practical takeaway: a week of work in a state with no threshold can create a return you owe. TaxFile prepares each state return you need at \$19 per state, and carries the credit for taxes paid to other states through to your resident return so you are not double-taxed. If you are unsure which state you were actually a resident of for the year, that is a residency question worth taking to a CPA rather than guessing.

State reciprocity agreements

A reciprocity agreement is a deal between two states, almost always neighbors, to tax cross-border workers based only on where they live. If you live in New Jersey and work in Pennsylvania, reciprocity means Pennsylvania does not tax your wages and your employer does not withhold Pennsylvania tax. You file in New Jersey and you are done. Some agreements cover all income, but most are limited to wages and compensation.

There are 30 reciprocal agreements in force across 16 states plus DC:

Reciprocity is not automatic on the employer side. You normally have to give your employer a nonresident withholding exemption certificate, and if you never did, the wrong state has been withholding all year. The fix is a nonresident return in the work state claiming a refund of everything withheld, plus a resident return at home.

Do not assume neighboring states have an agreement. Delaware is the clean counterexample: its Division of Revenue states plainly that Delaware maintains no reciprocity agreements, and Delaware residents working out of state must file with Delaware on top of the state where they worked.

What state filing costs and what TaxFile does not do

TaxFile charges \$39 for a simple return, \$89 for self-employed, and \$199 for business, plus \$19 for each state return. There is no free tier. If you worked in three states last year, that is three state returns at \$19 each on top of your federal plan.

Worth being straight about the limits. TaxFile prepares W-2, 1099, Schedule C and Schedule SE returns, federal and state. It does not e-file Form 4868 extensions, does not file amended returns on Form 1040-X, and does not handle capital gains on Schedule D, rental income on Schedule E, or crypto. If your return needs any of those, this is not the right tool for you this year.

For everyone else, the flow is the same as the federal side: upload your W-2s and 1099s, TaxFile reads them, prepares both returns, runs an error check, and shows you the finished return with a plain explanation of each line. It e-files through an authorized IRS e-file provider only after you approve. If you want to see the federal number first, run it through the tax refund calculator, or start with online tax filing and add your states from there. Self-employed filers with income sourced to several states should start at self-employed tax filing.