Why this is harder than it looks
Counting days sounds like primary-school arithmetic. In a real travel year — a few countries, some weekend hops, a visa run, one trip you have half-forgotten — it stops being simple. The rules that depend on the count each count slightly differently, and small errors compound: the Schengen 90/180 window, tax residency, and individual visa limits all have their own arithmetic.
Trap 1: partial days usually count as whole days
For most of the rules that matter, the day you arrive and the day you leave each count as a full day, whatever the hour. Two "half days" of travel are two whole days on the ledger, not one. Build that in from the start and a lot of accidental overstays simply disappear.
Trap 2: the window may be rolling
A "90 days" or "183 days" limit often isn't measured against a fixed block but against a window that moves. With Schengen it is the previous 180 days, recomputed every day. That means a trip from four months ago can still be sitting inside today's window — and compliance has to be checked continuously, not once a year.
Trap 3: passport stamps are not a reliable ledger
Stamps are date-only with no times, sometimes illegible, sometimes missing, and — as automated border systems expand — sometimes not applied at all. They were never meant to be your running total. Reconstructing a year of movement from stamps after the fact is exactly when mistakes creep in.
A simple system that holds up
You don't need a spreadsheet with twelve tabs. You need three habits:
- Record the edges. Note the date you enter and the date you leave each country, every time. The edges are where counts are won or lost.
- Count inclusively. Treat both edge days as full days unless you have a specific reason not to.
- Check against the right window. Know whether each rule uses a calendar period or a rolling one, and measure against that — not against a vague sense of "a few weeks".
Or don't count by hand at all
Every one of those traps is a place a phone does better than memory. Countly logs the edges automatically, counts inclusively, and recomputes each rolling window every day — per country, on your device. The point isn't to obsess over the number. It's to never have to.
General information only — not legal or tax advice.