Updated
Locks Do Not Meet The Insurance Standard
Your policy asks for British Standard locks and you have no idea whether the locks on your doors qualify.
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What's happening?
BS 3621 is the British Standards Institution standard for thief-resistant locks, and it is the one most home insurance policies name. Checking is genuinely simple: open the door and look at the faceplate on the edge of the lock. A lock that meets the standard carries the BSI Kitemark engraved on that faceplate along with the standard number and its year — BS 3621:2017+A1:2024, for example. No Kitemark and no number means it is not a British Standard lock, whatever the box said. The requirements behind it are specific: at least five levers with a minimum of a thousand key differs, anti-pick and anti-drill measures including hardplates, and a bolt throwing at least 20mm into the frame. That last point is why a three-lever mortice lock cannot be BS 3621, and why a five-lever lock is not automatically BS 3621 either — it has to have been tested and Kitemarked.
What usually causes it?
- The original locks predate the standard, common in older houses that have never been upgraded
- A three-lever mortice lock fitted where a five-lever Kitemarked one was needed
- A five-lever lock fitted that was never tested or Kitemarked to BS 3621
- A plain night latch on the front door with no British Standard deadlock alongside it
- Locks replaced quickly after a lockout with whatever the trader had in the van
- A back or side door left on its original builder's lock while the front was upgraded
- A previous owner's DIY lock change, fitted without reference to any standard
Is it dangerous?
Not physically, but the consequences arrive at the worst moment. Where a policy requires locks to a named standard, a claim after a break-in is the point at which the locks get examined. The standards also exist for a reason — they test resistance to drilling and picking, and a lock that has not been tested has not shown it resists either.
Can I fix it myself?
Checking is a five-minute job you can do yourself. Open each external door, look at the faceplate on the door edge, and note whether there is a Kitemark and a standard number. Do the same at the back door, the side door and any door from an integral garage. Fitting the locks is the part to hand over — the standard your policy names has to be matched exactly, and a lock that is close but not Kitemarked is no better than what you had.
When should you call a locksmith?
Call a locksmith when a door has no Kitemarked lock, when you cannot tell what is fitted, or when your insurer has named a standard and you want it evidenced on every door. Read your own policy first for the exact wording, because requirements vary between insurers and only they can tell you what your cover assumes.
What will the locksmith actually do?
- Survey every external door and record what lock and what standard is currently fitted
- Explain which doors fall short of the standard your policy names
- Fit Kitemarked locks to the correct standard, morticing and aligning them properly
- Use BS 8621 keyless-egress locks where a door is a single means of escape rather than a keyed one
- Confirm bolt throw and keep engagement on each door, and hand over a full set of keys
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