Landlord insurance often comes with a condition that is easy to miss until it matters: the policy specifies the locks that must be fitted, and if yours fall short, a claim can be refused. This guide explains the lock standards landlord insurers expect on a rental property — what BS3621 and TS007 actually mean, which doors need what, and how to make sure your let is covered rather than quietly non-compliant.
Insurers differ, and the wording in your policy is what counts. This guide explains the common standards so you know what to look for — then check your policy says exactly that, and fit to it.
An insurer is pricing the risk of a claim, and the locks on the doors are a direct lever on that risk. A door with a basic, snappable cylinder is far easier to defeat than one with an anti-snap lock to a recognised standard. So policies set a minimum lock specification as a condition of cover — meet it and you are protected; fall below it and the insurer can decline a theft claim on the grounds the condition wasn’t met. It is not about whether the lock “works”; it is about whether it meets the named standard.
BS3621 is the British Standard most insurers want on timber external doors. It covers key-operated locks — typically a five-lever mortice deadlock — that have passed testing for resistance to drilling, picking and forcing. A compliant lock carries the British Standard kitemark (a heart-shaped symbol) and the number BS3621 stamped on the faceplate or body. If your policy says “BS3621” and the lock has no kitemark, it almost certainly doesn’t qualify. Our guide to BS3621 locks shows what to look for.
Most modern doors are uPVC or composite with a euro cylinder, and the relevant standard there is TS007, rated in stars. The cylinder is the part burglars attack by snapping, so this matters enormously. There are two routes to full protection:
A basic, non-rated cylinder — the kind fitted as standard on many doors — can be snapped in seconds. If your policy expects anti-snap protection and you have a plain cylinder, you have a gap. See our guides to anti-snap locks and euro cylinders.
Timber door → BS3621 kitemarked mortice deadlock. uPVC / composite door → TS007 3-star cylinder (or 1-star cylinder + 2-star handle). Match the lock to the door and the policy.
Many policies also require key-operated locks on accessible windows — particularly ground-floor windows and any that can be reached from a flat roof, drainpipe or boundary. Patio and French doors, and any other vulnerable opening, may carry their own requirements. The principle is the same: the insurer specifies, and you fit to match.
If you ever need to claim, being able to show the locks met the policy is what protects you. After any lock work, keep a written record — ideally noting the standard fitted (BS3621, TS007 3-star) and the date. A good locksmith will give you that as a matter of course. It turns “I think they were compliant” into “here’s the proof”.
Beyond insurance, the wider direction of travel is toward higher landlord standards. The Renters’ Rights Act 2025 (in force since 1 May 2026) strengthened enforcement on property condition and safety. Keeping locks to a recognised standard isn’t just an insurance box-tick — it is part of running a property properly. Our guide to landlord lock and security responsibilities sets the wider picture.
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We fit locks to the exact standard your policy requires — BS3621, TS007 3-star, key-operated window locks — and give you a written record for your file, so your cover stays valid. One named local locksmith, fixed prices, no call-out fee. See our landlord locksmith services, or find your local locksmith to get your let checked.
A practical end-of-tenancy security checklist for landlords and agents: change the locks, check the standard, test windows, account for keys, secure outbuildings, revoke communal access and check fire safety.
For hands-on help, LocksmithLocal connects you with an accredited locksmith in your area.
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