# 90-180 days rule: Confused about carry over days and new start of 180 day period [duplicate]

I have a short question about the 90/180 day visa calendar. My girlfriend has visited the Schengen area according to below schedule:

• Arrival 28 July 2017

• Departure 10 October 2017

• So she basically still has 15 days left from that previous stay.

She now however is in compliance to the requirements needed to start the procedure to grant her 5-years stay, but I am struggling to understand

1. when the new 180 days period start for her
2. if these 15 days can be carried over (are still to be used) in the current 180 days.

My basic question is: What is the earliest date for her to come again, and then stay for another 90 days (in a new 180 days period)?

• The 180 days is a rolling window. – Roddy of the Frozen Peas Dec 4 '17 at 13:38
• Thank you, but what is that supposed to mean? Or do you mean, she can now already come and a new 180 day period will start again? – Rene1966 Dec 4 '17 at 13:43
• Thinking about 180-day periods is not that helpful, you should really check some online calculator and try different parameters (see the link in the other answer). – Relaxed Dec 4 '17 at 14:03
• Which kind of 5-year stay are you thinking about? Depending on the answer, the 90/180 restriction might be irrelevant. – Relaxed Dec 4 '17 at 14:13

1. Thinking about a single 180-day period is unhelpful. The 180-day period is a rolling window, meaning you have to consider all possible 180-day period (the one from July 28 to January 23, the one from July 29 to January 24, etc.) and make sure the person is never present for more than 90 days in the Schengen area in any of these periods.

2. The 15 days left are not “carried over” per se and definitely would not allow her to stay longer than 90 days in one go under short-stay rules. But they do allow her to come earlier to start another 90-day stay or to make a separate 15-day stay in-between.

In practice, I often get confused, the best solution is to use a calculator. If I entered the parameters correctly, it seems your girlfriend could come back on January 9 (not coincidentally 180 - 14 days after July 28 or 15 days before January 23).