Lost Keys in Shared Flat: Tenant Tips Germany

Liability & Household Insurance 3 min read · published September 07, 2025

Losing keys in a shared flat can quickly lead to insecurity, access problems and costs. As a tenant in Germany, stay calm and act methodically: inform flatmates and the landlord immediately, check for related risks (e.g. lost ID badges) and decide whether locks need to be changed right away. This guide explains who in a shared flat typically bears liability, when the landlord must consent, which forms and deadlines matter, and how to collect evidence to avoid or reclaim costs. The guidance takes into account German legal basics and shows practical steps so that you as a tenant can assert your rights and avoid unnecessary expenses. If unsure, seek legal advice.

What to do after losing keys in a shared flat

First: remain calm and act quickly. Inform all flatmates and check if a spare key exists. Report the incident to the landlord, especially if keys had name tags or access codes. For questions about tenant and landlord duties see the statutory rules in the BGB.[1]

Keep a spare key with a trusted person to avoid access outages.

Immediate steps

  • Inform flatmates and check for an available spare key.
  • Contact the landlord and describe which keys were lost.
  • Check whether door keys were tagged with names or combined with access cards.
  • Document time, place and circumstances of the loss with photos or short notes.
  • Decide whether a temporary locksmith visit or a full lock change is necessary.
If you suspect misuse, report it immediately to the police.

Costs and liability

Who pays for a new lock or key copy? Often the person responsible for the loss bears the costs. For keys used jointly in a shared flat, splitting costs is often reasonable. If a lock change is necessary due to a security risk, the landlord may be obliged to act at their expense; the precise allocation is governed by the BGB.[1]

Replacing locks and landlord consent

Tenants should not make permanent changes to locking systems without the landlord’s consent. Replacing an entire locking system often affects the landlord’s property; therefore, always discuss with the landlord and keep written agreements. Request receipts and invoices for any repairs to document expenses.

Written agreements with the landlord protect against later claims for costs.

If no agreement: legal steps

If no agreement is reached and costs arise, tenants can examine claims and, if necessary, assert them in court. The local court (Amtsgericht) is usually responsible for tenancy disputes in first instance; procedural rules follow the Code of Civil Procedure.[2][3]

FAQ

Who pays if a flatmate loses the key?
Generally the person at fault; if unclear, flatmates should agree on a fair cost split or consult the landlord.
Can I replace a lock without permission?
No, not without the landlord’s consent, especially for permanent changes to the locking system.
What evidence helps avoid costs?
Photos, timestamps, witness statements from flatmates and invoices for replacement measures.

How-To

  1. Inform flatmates and the landlord immediately and document the loss.
  2. Check if a spare key exists or if a locksmith visit is needed.
  3. Obtain written cost estimates and keep receipts.
  4. If the landlord will not cooperate, check legal options at the competent local court.

Help and Support / Resources


  1. [1] Bürgerliches Gesetzbuch (BGB) §§ 535–580a
  2. [2] Zivilprozessordnung (ZPO)
  3. [3] Federal Court of Justice (BGH)
Bob Jones
Bob Jones

Editor & Researcher, Tenant Rights Germany

Bob writes and reviews tenant law content for various regions. They’re passionate about housing justice and simplifying legal protections for tenants everywhere.