The Schengen 90/180 rule, explained so you can actually count it

If you can enter the Schengen Area without a visa, you may stay up to 90 days in any 180-day period. The trap is in the phrase "any 180-day period", which is not the same as "the last six months" or "per calendar year".

How the count actually works

The 180-day reference period is not fixed. On each day of your stay you look backwards 180 days and add up the days you were inside the area. That total must never exceed 90.

• Your day of entry counts as a full day of stay.
• Your day of exit also counts as a full day of stay.
• Days that have dropped out of the backwards 180-day window no longer count against you.
• A continuous absence of 90 days restores a full new 90-day allowance.

A worked example

1. 1You spend 60 days in the area in spring and leave.
2. 2You come back 40 days later. Those 60 days are still inside the backwards window, so you have 30 days left, not 90.
3. 3Only once the earliest of those spring days falls outside the 180-day window does that allowance start returning, day by day.

Where it goes wrong

• Treating the window as a calendar half-year, so the count appears to reset on a fixed date. It does not.
• Counting only full days and ignoring the arrival and departure days.
• Assuming a short hop out of the area resets the clock. It does not.
• Mixing up the Schengen Area with the EU. They are not the same list of countries.

The European Commission publishes an official short-stay calculator with both a check mode and a planning mode. When a trip is anywhere near the limit, use it rather than counting by hand.