Can my landlord or Hausverwaltung find out about my Abmeldung?

honestly, they *can* but it's not automatic. the Bürgeramt doesn't send out notifications when you deregister, so your landlord only finds out if they specifically request a Melderegisterauskunft. that costs like 5-10 euros and requires a "berechtigtes Interesse" which is a bit of a hurdle for them unless they suspect something shady. if you're on good terms and just moving out normally, they usually don't bother. just make sure you hand over the keys on time and get a Übergabeprotokoll signed so there's no confusion about the move-out date

The short answer is yes, they can. When you abmelden, the city's registration office (Bürgeramt) updates your data in the Melderegister, which is technically a public register. Landlords or Hausverwaltungen can request a simple Melderegisterauskunft to see if you are still registered at your old address, though they need a legitimate interest to do so, like proving you've moved out if you're still on the lease. In practice, most don't bother unless there's a dispute over something like a rent increase or termination notice. If you're really worried, you can file a Sperrvermerk to block these inquiries, but you'll need a valid reason like stalking or harassment.

They won't proactively find out from the Bürgeramt, but the real issue is usually the GEZ and your bank. If you abmelden and don't update your bank address, your landlord might see returned bank statements or official post. I've seen cases where the Hausverwaltung only found out because a forwarded letter from the Finanzamt showed a new address. If you're trying to stay registered somewhere else while keeping this flat, that's a different story and gets complicated with the Anmeldung requirements.

My understanding is that the Melderegister is a public register in a limited sense, so anyone with a "berechtigtes Interesse" can request a simple data extract. Your landlord would need to argue that they have a legitimate need to know, like if you owe utilities and they're trying to locate you. I'd say the bigger risk is if you're still on the lease and the Hausverwaltung sends official mail to your old address after you've deregistered, because then it might come back as undeliverable and raise questions.

Technically yes, the Bürgeramt can share that data with other offices, but in practice it rarely gets back to landlords unless there's a specific reason like a police investigation or a court order. The Meldebehörde isn't in the business of notifying your Hausverwaltung about every address change. That said, if you're still on the lease and the landlord sends official mail that bounces back, they might start asking questions. Best to handle it directly with them if you're moving out properly, otherwise you're just inviting a headache.