Guides

Residency rules, in plain English.

How the day-count rules actually work, for expats, nomads and anyone whose tax home depends on a calendar.

Travel

The Schengen 90/180 rule, explained

How the Schengen Area's rolling 90-days-in-180 limit really works, why counting from your entry date gets it wrong, and how to know when your next day frees up.

Oct 6, 2026 Read →

Tax residency

The US Substantial Presence Test: how the 183-day formula works

Why you can become a US tax resident without spending 183 days in the US in one year, and how the three-year weighted formula adds up.

Sep 22, 2026 Read →

Tax residency

The 183-day rule: what it means, and what it doesn't

Staying under 183 days is the best-known residency rule and the most misunderstood. Where it applies, where it doesn't, and what else tax authorities check.

Sep 8, 2026 Read →