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183-day rule calculator

Enter how many days you spent in a state and whether you keep a home there. The calculator applies the two-prong statutory-residency test and tells you where you stand. Everything runs in your browser.

Days present in the state this year You maintain a permanent place of abode in this state

How statutory residency works

A state can tax you as a full-year resident, on all of your income, under either of two independent tests: domicile (your one true permanent home) or statutory residency. The statutory test is mechanical and catches people who "moved" but kept ties. You are a statutory resident if both are true:

you maintain a permanent place of abode in the state (a home suitable for year-round use), and
you are present there more than 183 days in the year — so 184 or more triggers it; exactly 183 generally keeps you a nonresident.

Because the trigger is "more than 183," treat 183 as the last safe day, not the first unsafe one. And remember New York and several states count any part of a day as a full day.

Frequently asked questions

What is the 183 day rule?

It is the day-count threshold most US states use for statutory residency: spend more than 183 days in a state while keeping a permanent place of abode there, and the state can tax you as a full-year resident regardless of where you claim to live. 183 days is just over half the year, the line that decides where you "really" live.

Is it 183 days per calendar year?

In most states, yes: the count runs over the tax (calendar) year and resets on January 1. A different flavor of 183-day rule applies internationally: many countries, and the US federal Substantial Presence Test, use their own versions with different windows and weights.

What counts as a day?

In New York and several other states, any part of a day counts as a full day; landing at 11 pm uses a whole day. A few states carve out narrow exceptions (travel through, medical stays). That is why an automatic day log beats a calendar reconstruction in an audit.

Not tax advice. Residency rules and the definition of a "day" vary by state and are fact-specific. This tool checks the common two-prong test only. Confirm your situation with a qualified advisor.

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Not sure how many days you've actually spent there?

SpyglassBeacon counts your days in every state automatically and warns you before you cross the line.

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