Guide, 7 min read
The 183-day rule: what it means and what it does not
"Stay under 183 days and you are not a tax resident." It is the most repeated travel tax myth. The number is real, but the rule around it is different in every country.
Updated 30 September 2026. This guide explains general rules. It is not legal or tax advice.
Where 183 comes from
183 days is just over half a year. Many countries treat you as tax resident if you spend 183 days or more there, and many tax treaties use the same number. But it is usually only one of several tests. You can be tax resident with far fewer days, for example because your home or family is there.
Three questions that change the answer
- Which period? A calendar year, a tax year that starts in April or July, or any rolling 12 months.
- What counts as a day? Some countries count any part of a day. The UK mostly counts where you are at midnight.
- What else is tested? A permanent home, where your family lives, where you work, or where your "centre of vital interests" is.
Example 1: the United States
The US Substantial Presence Test does not use a simple 183 days in a year. You meet it if you were in the US for at least 31 days this year, and the total of these three numbers is 183 or more:
- all the days you were in the US this year,
- one third of the days last year,
- one sixth of the days the year before.
There are exceptions, such as the closer connection exception (IRS Form 8840) and days that do not count for certain visa holders. US citizens and green card holders are taxed on a different basis entirely.
Example 2: the United Kingdom
The UK uses the Statutory Residence Test. In short:
- You are automatically UK resident if you spend 183 days or more in the UK in the tax year (6 April to 5 April).
- You are automatically not resident if you spend fewer than 16 days (or fewer than 46 days if you were not UK resident in any of the three previous tax years), or if you work full time abroad and meet the conditions.
- Otherwise, the sufficient ties test compares your days with your ties to the UK, such as family, a home, work and past years. With more ties, fewer days are allowed.
A day usually counts if you are in the UK at the end of the day (midnight), with special rules for transit and exceptional circumstances.
What this means for your record
For every country, the safest record is a daily one: where you were each day, with the evidence behind it. From a daily record you can answer any version of the rule. From "about four months in Spain" you cannot.
Countr keeps that daily record and has 67 tax trackers, including the UK SRT, the US Substantial Presence Test and about 30 US state rules. It counts the days. For the final answer on residence, talk to a qualified tax adviser.
Official sources
Countr can count this for you.
It finds your past trips in your photos and counts the days for every rule you follow, on your phone.