Schengen 90/180 -laskuri

What the 90/180 rule actually says

The limit is set by the Schengen Borders Code, and the wording matters more than the summary: it is not 90 days per visit, per country, or per calendar half-year.

The clause that catches people out is the last one. The 180-day period is recalculated for every single day you are present, so the window slides forward with you rather than resetting after a trip.

How the window is measured

Four mechanics follow from that wording, and together they decide your number:

• The window looks backwards, never forwards. On any given day you count the Schengen days in the preceding 180, including that day.
• Both travel days count as full days of stay, no matter what time your flight landed or left.
• Days drop out one at a time, as they age past the 180-day boundary, which is why your allowance recovers gradually rather than all at once.
• The count is per person, not per passport, and it follows you across every Schengen state rather than restarting at each border.

Where the rule came from

The rolling window replaced an older formulation that allowed three months in a six-month period measured from the date of first entry. That version reset, which made it far easier to plan around and far harder for border officers to verify. The rolling test has applied since October 2013.

A worked example

Three trips, and a reference date of 1 August. The 180-day window ending that day opens on 3 February, so the January trip has already aged out.

• Trip 1: 5 to 20 January, 16 days.
• Trip 2: 3 to 25 March, 23 days.
• Trip 3: 1 to 30 June, 30 days.

How to read that

On 1 August you have used 53 of your 90 days, so 37 remain. The 16 days in January are not forgiven, they have simply aged out of the window that applies today.

The March days go the same way. They leave the window one at a time through late August and September, and your allowance climbs back as they do.

This is why a trip that looked safe when you booked it can breach the limit by the time you travel: the window that will apply on your arrival date is not the one that applies today.

Common mistakes

Almost every overstay we hear about comes from one of these five assumptions:

• Treating the window as fixed. There is no half-year that resets on 1 January or on the date of your first entry. Every day of stay gets its own backward look.
• Not counting travel days. A flight that lands at 23:50 and one that leaves at 00:10 each cost a full day.
• Assuming a second passport resets the count. The 90 days attach to the traveller, not the document, and the Entry/Exit System is built to match people rather than booklets.
• Confusing Schengen with the EU. Ireland is in the EU but outside Schengen; Switzerland, Norway and Iceland are in Schengen but outside the EU. Only Schengen days count here.
• Reading a residence permit as an exemption. A national long-stay visa or permit covers the issuing country. Time in the other Schengen states is generally still measured against the 90/180 limit.

Go deeper

The rule is short, the edge cases are not. These go further:

• Schengen 90/180 explained, , the full walkthrough with more worked examples.
• Schengen overstay penalties, , what actually happens at the border and afterwards.
• Can a second passport reset your Schengen count? , the short answer and why people believe otherwise.
• The Schengen rules guide, , how the area fits together and who it applies to.
• Spain 90-day calculator, , for the single most searched-for country version of this rule.
• Multi-country day counter, , if you are tracking Schengen alongside a tax-residency threshold.