Upvote:13
Letβs make it clear: you can have however many citizenships and passports, as long as the 90/180 rule applies to you, it applies to you, not each of your citizenships or passports separately.
So, no, coming back on a different passport does not reset anything.
Yes, it will be harder for a border official to determine whether you are or arenβt within your allowance, as currently the only simple way they have is to check stamps in your passport and count the days, so like if you renewed a passport, they will only get part of the picture.
But if they become suspicious for whatever reason, dig a bit further, and find out your other passport or find traces of your presence in Schengen via other means, then you could be in big trouble. Not only could you be turned away immediately, but you may have difficulty ever coming back.
Of course this will become a lot easier for them once the forever-delayed EES and ETIAS come into force, but even before then, itβs just not allowed.
But in any case, 3 weeks and then another week sometime later is well within the 90/180 limit, with months to spare.
Upvote:14
Officially your time in the Schengen area is per person, so added for both passports.
In practice people sometimes report that using two passports the border officials ignored the one not in their hands.
On the other hand, I have also heard of people who were asked about other nationalities and had to proof they had not overstayed their 90 days.
In the future a system with computer registration will be started, which should keep track of your time in Schengen and then you will not be allowed to add the time on the two passports.