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Lost House Keys
Your keys have gone missing or been stolen, and you do not know who has them or whether they can find your address.
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What's happening?
Losing keys is a security decision rather than a repair. The question is not whether you can get in — a spare or a locksmith solves that — but whether the missing key can still open your door and whether anyone can connect it to your address. That risk rises sharply when the keys were lost with anything identifying: a wallet, a bag with post in it, a phone with your address saved, a keyring with a house number or a fob for a specific block. It also matters if the keys were taken rather than dropped. What a locksmith actually changes depends on the lock: on a euro cylinder door the barrel is swapped and the old keys are dead, on a mortice lock the whole lock or its levers change, and on a night latch the rim cylinder is replaced. None of it requires a new door.
What usually causes it?
- Keys dropped in the street, on transport or at work with no way of tracing them
- A bag, coat or wallet stolen with the keys inside
- Keys handed to a tradesperson, a cleaner, a letting agent or a previous tenant and never returned
- A keyring lost with an address label, a fob, or documents that identify the property
- A spare left with someone you no longer trust with access
- Keys taken in a burglary, sometimes fished through a letterbox
- One of a set missing, with no certainty which door it opened
Is it dangerous?
Treat lost keys as an access risk until you know otherwise. Where they were lost with anything identifying, or where they were stolen, the property should be regarded as open to whoever holds them. Insurers commonly expect reasonable steps to be taken once keys are lost, so changing the locks is both the sensible response and often the one your policy assumes.
Can I fix it myself?
Retrace and report first — many keys are handed in, and reporting a theft to the police gives you a crime reference number your insurer is likely to ask for. Beyond that, changing a lock yourself is where people go wrong. A euro cylinder has to be the right length for the door so it does not protrude, and a mortice lock has to match the standard your insurer requires. Fitting the wrong one leaves you with a lock that looks new and secures less than the old one.
When should you call a locksmith?
Call a locksmith the same day where keys were stolen, lost with identifying information, or never returned by someone who had access. Ask for locks that meet the standards your insurer requires, and have every external door done at once — a back door or a side gate on the old key defeats the whole exercise.
What will the locksmith actually do?
- Establish which doors the missing keys opened, including side gates, garages and outbuildings
- Replace euro cylinders, rim cylinders or mortice locks so the missing keys no longer work
- Size euro cylinders correctly for each door so nothing protrudes and invites snapping
- Fit locks that meet the standards your insurance requires and confirm what is now on each door
- Key doors alike where you want a single key, and supply a full set of new keys
Frequently asked questions
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