The Schengen 90/180-day rule, explained
If you visit the Schengen Area visa-free, you can stay at most 90 days in any rolling 180-day window — counted across the whole area, with both your arrival and departure days counted as full days. Here is how that actually works, and the 2026 changes worth knowing.
Read & calculate → Tax residencyThe 183-day tax residency rule, explained
"183 days" is the most famous number in cross-border life, but it's a starting point, not a finish line. The exact threshold, the period it's measured over, and how each day is counted change from country to country and from treaty to treaty.
Read & calculate → UK tax residenceThe UK Statutory Residence Test, explained
The UK decides tax residence with a structured set of tests applied to each tax year (6 April to 5 April). Spend 183 days or more in the UK and you are automatically resident — but you can also become resident on far fewer days through the sufficient-ties test. Here is how the pieces fit together.
Read & calculate → US state tax residencyUS statutory residency: the 183-day + permanent-home test in NY, NJ, CT, MA and PA
Five US states can tax you as a full-year resident purely on the basis of time plus a home, even if your real life is somewhere else. This is the "statutory residency" rule, and it is separate from where you are domiciled. Here is how it works across New York, New Jersey, Connecticut, Massachusetts and Pennsylvania, in plain language.
Read & calculate → New York ruleThe New York 183-Day Rule: Statutory Residency Explained
New York can tax you as a resident even if your real home is somewhere else. If you keep a permanent place to live in the state and spend more than 183 days there in a year, you can become a "statutory resident" — a separate test from where you are domiciled. New York City applies its own version of the same rule.
Read & calculate → California state taxCalifornia Residency for Tax: The Nine-Month Presumption Explained
California does not have a clean "183 days and you're a resident" rule. Instead, spending more than nine months in the state in a tax year creates a rebuttable presumption that you're a resident — and residency itself is decided by a facts-and-circumstances test, not a day count.
Read & calculate → Canada tax residencyCanada's 183-Day Rule, Explained
If you spend 183 days or more in Canada during a calendar year without strong ties there, the Canada Revenue Agency can treat you as a "deemed resident" for the whole year — and tax your worldwide income. But day-counting is only one of two routes into Canadian tax residence, and a tax treaty can override the result.
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