Should you change the locks when you move in?
Last reviewed 2 October 2026 by the Swansea Locksmith Quotes team
The short answer
Yes, in most cases. You rarely know how many keys to the old locks exist: previous owners, tenants, builders and neighbours may all have had copies. Changing euro cylinders on uPVC or composite doors is usually a quick job, and it is a chance to fit cylinders rated against lock-snapping. Renters need their landlord’s permission first.
Step by step
- List every external door, including back, side and garage doors.
- Check the door type and lock on each. A photo of each lock helps the quote.
- Renters: ask your landlord or agent in writing before changing anything, and agree who keeps a key.
- Ask whether the new cylinders are rated against snapping, for example to TS007 3-star or SS312 Diamond, if your insurer asks for a standard.
- Keep a note of how many keys you were given and who has them.
Owners
You can change the locks whenever you want. Check your home insurance wording. Some policies specify the lock standard on the final exit door.
Tenants
Your tenancy agreement normally needs the landlord to agree to a lock change. If you have a safety concern, put it in writing, and the landlord can arrange it.
Flats and shared entrances
The main entrance door to a shared building is usually managed by the landlord or the managing agent. You can normally only change your own flat door.
When to get help
Request quotes for all doors at once. It is usually cheaper than separate visits.
General guidance only. If anyone is in danger, or you smell gas, call the emergency services first.