SojournalThe 183-day rule
There is no single 183-day rule. Many countries and US states use a figure near 183 days, but each counts days its own way, over its own period, and days are rarely the whole test. Here is how the main ones work, with the official source for each.
Not the same as Schengen 90/180. That is an immigration rule about how long you may stay; the 183-day rules are about tax and residence. For Schengen, use the Schengen calculator.
Two questions decide the count
What counts as a day?
Most rules count any part of a day: arrive at 23:00 and that day counts. The UK counts only days on which you are in the country at midnight. Portugal counts nights.
“183 or more”, or “more than 183”?
The US federal test and Canada need 183 days or more. New York and Spain need more than 183, so 184. One day makes the difference, so the wording matters.
Rule by rule
| Where | The day test | Period | Source |
|---|---|---|---|
| United States (federal) | At least 31 days this year, and days this year + 1/3 of last year + 1/6 of the year before reach 183 (Substantial Presence Test). Any part of a day counts. | Calendar year, 3-year weighting | 26 U.S.C. §7701(b)IRS Publication 519 |
| New York | More than 183 days in the state and a permanent place of abode there. Any part of a day counts. | Calendar year | NY Tax Law §605(b) |
| United Kingdom | 183 days or more makes you resident automatically (Statutory Residence Test). A day counts if you are in the UK at midnight. | Tax year, 6 April to 5 April | Finance Act 2013, Sch. 45 |
| Canada | Sojourning 183 days or more in total makes you a deemed resident for the whole year. Any part of a day counts. | Calendar year | Income Tax Act s. 250 |
| Spain | More than 183 days in Spain. Sporadic absences count as days in Spain unless you prove tax residence elsewhere. | Calendar year | Ley 35/2006 (LIRPF) art. 9 |
| Portugal | More than 183 days, counting days that include a night in Portugal. | Any 12-month period starting or ending in the year | CIRS art. 16 |
| Italy | Physical presence for the greater part of the year (183 days, 184 in a leap year). Fractions of a day count. | Calendar year | TUIR art. 2 |
| Germany | A continuous stay of more than six months; short interruptions don’t break it. No fixed 183-day count. | Any six months, can span two years | § 9 AO |
| Türkiye | Living in Türkiye continuously for more than six months within one calendar year. Temporary departures don’t break the stay. | Calendar year | Gelir Vergisi Kanunu art. 4 |
| Netherlands | No day count for tax: residence depends on the circumstances. Separately, you must deregister from the BRP if you expect to be abroad at least 8 months in a year. | Circumstances; BRP: 12 months | AWR art. 4Wet BRP |
Days are only part of the test
Most countries also look at your permanent home, your family, your work and where your life is centred. You can be resident with fewer days, or not resident with more. When two countries both treat you as resident, the tax treaty between them decides, using its own tie-breaker tests.
Tax treaties also have their own 183-day rule for employees, which decides where salary is taxed. It is a different test from the residence rules above.
Keep a record that holds up
In a residency audit, you usually have to prove your days. New York’s auditors ask for phone records, card statements and calendars, and you must show fewer than 184 days. A day-by-day record made at the time, with receipts or boarding passes attached, is far easier to defend than a list rebuilt later from memory.
This page summarises published rules and links the official texts. It is not tax or legal advice. Rules change and have exceptions; ask a tax adviser about your own case.
Sources checked: October 2026.