If you've ever read through your home insurance policy carefully — and most people haven't — there's a reasonable chance it contains a clause about the type of locks fitted to your doors. Miss it, and you could find yourself making a claim only to be told it won't be paid out, because the lock on your front door didn't meet the standard your insurer specified when you took out the policy.
It's one of those details that seems bureaucratic until the moment it matters. Here's what British Standard locks actually are, why insurers care about them, and what to do if you're not sure whether your home is covered.
What Does "British Standard" Actually Mean?
A British Standard lock is one that has been independently tested and certified to meet a specific security specification published by the British Standards Institution (BSI). For door locks, the two most commonly referenced standards are:
- BS3621 — the long-established standard for mortice deadlocks and rim locks. A BS3621 mortice lock must have at least five levers, a hardened steel bolt, and anti-drill protection, among other requirements. The standard covers both the lock mechanism and its resistance to various methods of forced entry.
- TS007 — a more recent standard that applies to euro cylinder locks, which are the type used in most modern uPVC and composite doors. Cylinders are rated one, two, or three stars under TS007, with three stars being the highest. A three-star cylinder must resist picking, drilling, snapping, and bumping to be certified.
Both standards exist because not all locks are created equal. A cheap euro cylinder fitted to an otherwise solid door can be snapped open in seconds using nothing more than a pair of pliers and a screwdriver — a technique so well known among burglars that it's now the most common method of forced entry to uPVC-doored homes in the UK. A certified anti-snap cylinder is specifically engineered to prevent this.
Why Insurers Specify These Standards
Home insurers are, at their core, risk businesses. The lower the likelihood of a claim, the more comfortable they are offering cover and the lower the premium they need to charge. British Standard locks reduce the probability of a successful break-in — and therefore reduce the probability of a burglary claim — so insurers have a direct financial incentive to encourage their use.
Most standard home insurance policies include a security clause that either recommends or requires British Standard locks on all external doors. Some policies word this as a condition of cover, meaning that if you suffer a break-in and your locks don't meet the standard, your insurer may refuse to pay the claim on the grounds that the property wasn't adequately secured. Others word it as a warranty, which has similar implications.
The specific wording varies between insurers, which is why it's worth reading your policy documents rather than assuming. Phrases to look out for include "five-lever mortice deadlock," "BS3621," "TS007 three-star cylinder," or simply "British Standard approved locks on all external doors."
Which Doors Does It Apply To?
Most policies that specify British Standard locks mean all external doors — front, back, and side. Some also include garage doors that connect directly to the house. French doors, patio doors, and doors into conservatories that lead into the main property are often included too.
Internal doors are not typically covered by these clauses, but it's worth checking your specific policy if you're uncertain. When in doubt, call your insurer and ask them directly which doors they require compliant locks on. Get the answer in writing if you can.
How to Tell Whether Your Locks Already Comply
For mortice locks — the type fitted into the body of a timber door — look for a keyhole on the door face (not just a Yale-style latch). A BS3621 compliant lock will usually have the BSI Kitemark stamped on the faceplate, which is the small metal plate visible on the edge of the door when it's open. If you can't see a Kitemark, it's likely not certified.
For euro cylinders — the oval barrel that sits in the face of most uPVC and composite doors — look for star ratings stamped on the cylinder itself, usually visible once the door is open. A single-star or unrated cylinder almost certainly doesn't meet TS007 requirements. A three-star cylinder will be clearly marked.
If you're not sure, a locksmith can assess your locks in a few minutes and tell you exactly where you stand. It's a straightforward question with a straightforward answer.
Worth knowing: The Kitemark is a registered trademark of the British Standards Institution. If a lock claims to be British Standard but doesn't carry the Kitemark, it hasn't been independently verified. The mark matters — the claim alone doesn't.
What Happens If Your Locks Don't Comply
If you discover your locks don't meet your insurer's requirements, the sensible thing to do is upgrade them before you need to make a claim rather than after. Upgrading a euro cylinder to a three-star TS007 model is one of the quickest and least disruptive security improvements you can make to a home — in most cases it takes under an hour and requires no changes to the door itself.
For older timber doors with a basic rim latch (a Yale-type lock), upgrading to a BS3621 five-lever mortice deadlock is a more involved job but still well within the scope of a standard locksmith visit. The lock is fitted into the door body, a strike plate is fitted to the frame, and the job is done.
It's also worth telling your insurer once upgrades are complete. Some will reduce your premium as a result, and it creates a clear record that the property met their security requirements at the time of any future claim.
A Note on New-Build and Rented Properties
New-build homes and rental properties sometimes cause confusion here. A brand-new uPVC door doesn't necessarily mean a compliant cylinder — developers don't always fit the highest-specification locks as standard, and the cylinder that comes with the door from the factory may be a basic one-star or even an unrated model.
If you've recently moved into a new build, it's worth checking the cylinders regardless of how new the doors are. Similarly, if you rent your home and are responsible for insuring the contents, check whether your contents policy has a security clause — and if it does, check with your landlord whether the locks comply. If they don't, your landlord is typically responsible for upgrading them.
Getting Your Locks Upgraded in Stourbridge
At AMP Lock we carry BSI 3 Star TS007 cylinders and BS3621-approved mortice locks as standard stock, so in most cases the upgrade can be carried out on the same visit without needing to order parts. We can advise on exactly which lock is right for your door type, confirm whether it meets your insurer's requirements, and fit it the same day.
If you're not sure what you currently have, send a photo of the lock via WhatsApp and we'll tell you straight away. Call or message on 07961 169 681 — no call-out fee, and pricing confirmed before we start.