DE-REGISTRATION IN BREMEN – Before leaving Germany for good you have to de-register again. You can either go to the local authorities in person (BSU or Bürgerservice Center) or you post your deregistration by (analogue) mail. If you go in person, bring your passport. If you post the document for de-registration, enclose a copy of your passport (both sides). Please make sure you deregister yourself no later (and not earlier) than one week before you leave.
If you move to a different city within Germany, you do not need to de-register, as the authorities will do that for you as soon as you re-register yourself as a new citizen.
Below you can download the document which you have to fill in on order to de-register in Bremen.
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