Why states matter
A state can tax you as a resident even when you've kept your federal days in order. The classic trap is the statutory-resident test: keep a home in the state and spend more than a threshold number of days there, and you're a resident for the year — regardless of where you're domiciled. New York's auditors are famous for it, counting days from phone records, E-ZPass tolls, and credit-card trails. The day count is exactly the kind of thing a spreadsheet loses and an audit finds.
How the 51 break down
Sojourn classifies every US jurisdiction into one of three shapes, so you always know what you're being measured against:
- Day-count states — 25 of them. A hard threshold plus, in most, a permanent home in the state. Cross the line and you're a statutory resident. These are the ones Sojourn watches most closely — New York, New Jersey, Connecticut, Massachusetts, Pennsylvania and California's neighbours among them.
- Facts-and-circumstances states — 17. No single number decides it; the state weighs where your life actually is. Sojourn surfaces the test and links the official guidance, because this is precisely the case a professional should read with you.
- No state income tax — 9. Florida, Texas, Washington, Nevada and the rest. Nothing to count — but Sojourn still records your presence, because a day in a no-tax state is a day you were not somewhere that does tax.
New York, as an example
New York's statutory-resident rule: if you are not domiciled in New York but you maintain a permanent place of abode there and spend more than 183 days of the year in the state, you are taxed as a resident. Arrival and departure days both count. Sojourn shows you the running count against that line, flags when you're within reach of it, links the New York Department of Taxation's own definition — and keeps the record you'd hand an examiner.
The same record, one app
State days live in the same audit-ready log as your countries. Log a state stay the way you log a country stay; each tracked state gets its own clock. Export it and the states appear in the same checksummed PDF, so you hand over one document, not several. If you're a US resident, Sojourn turns tracking on when you register — it's part of the Pro tier. Pro
Honesty first — this is not tax advice
State residency is high-stakes and fact-specific, and the rules change. Sojourn summarises each state's test and links its official source so you can read it yourself, but every state surface in the app carries the same line, and so does this page: this is a record-keeping tool, not tax advice. Before you rely on any of it, confirm your position with a qualified tax professional. Where a state's classification is still being confirmed, the app says so rather than pretending to certainty it doesn't have.