BS3621 Locks and Your Home Insurance

BS3621 is a British Standard published by the British Standards Institution that sets out the minimum security performance a lock must meet to be considered suitable for external doors on domestic properties. The 'BS' simply stands for British Standard, and 3621 is the document number. A lock that carries this kitemark has been independently tested to resist specific attack methods — including picking, drilling, and manipulation — to a defined level. The standard applies primarily to mortice deadlocks (what most people call a deadlock or a mortice lock), and also covers some rim deadlocks and cylinder deadlocks.

Insurers ask for BS3621 because burglary statistics consistently show that a significant proportion of break-ins happen through the front door. A lock that meets BS3621 is meaningfully harder to defeat quickly, and insurance underwriters price that risk accordingly. If your policy states that external doors must be fitted with a BS3621 lock and yours is not, your insurer may reduce any burglary-related payout — or decline the claim altogether. That is not a theoretical risk; it happens, and it is worth taking seriously before you need to make a claim rather than afterwards.

The most straightforward way to check is to look for the kitemark on the lock body itself. On a mortice deadlock, open your front door, unscrew the faceplate (the vertical metal strip on the edge of the door), and look at the body of the lock. A genuine BS3621 lock will have the BSI kitemark — a stylised kite shape containing the letters 'BS' — stamped or cast into the metal, usually alongside the number 3621. Some locks also carry it on the faceplate or on a small label inside the casing. If the lock is old, the marking may be worn, so look carefully with a torch.

If you have a uPVC or composite door, the situation is slightly different. These doors typically use a multipoint locking mechanism — a long strip of bolts, hooks, and rollers that engage at several points up and down the door frame when you lift the handle and turn the key. Multipoint locks on uPVC doors are not mortice deadlocks, so they do not carry a BS3621 kitemark in the same way. However, the euro cylinder that operates the lock — the oval barrel you insert your key into — can and should meet a recognised security standard, most commonly TS007 3-star. If you have a uPVC door, check your policy wording carefully: many modern policies accept a TS007 3-star cylinder combined with a multipoint lock as an equivalent. If in doubt, call your insurer and ask them to confirm in writing what they require for your specific door type.

One issue that has become much more prominent over the past decade is cylinder snapping. Many uPVC and composite doors in Rainham — particularly those fitted during the 1990s and 2000s — were installed with standard euro cylinders that protrude beyond the door furniture. A burglar can use a simple technique (which we will not detail here) to snap the cylinder in seconds and open the door without picking a single pin. Streets around the Rainham town centre, as well as properties along the Ferry Lane corridor and on the Orchard Village estate, are all fitted predominantly with uPVC doors of this era, and cylinder snapping has been a known method of entry in the RM13 area.

The solution is to replace a vulnerable cylinder with an anti-snap, anti-pick, anti-drill cylinder that carries the TS007 3-star rating. These cylinders are engineered to break in a controlled way at a sacrificial point, leaving the internal lock mechanism intact and the door secure. If your uPVC door lock currently has a plain, unmarked euro cylinder that sticks out beyond the door handle or escutcheon plate, it is very likely not snap-resistant. A door lock replacement Rainham carried out by our team takes around 20 to 30 minutes and uses a correctly sized, security-rated cylinder — we measure the existing cylinder first so the replacement fits precisely and the lock operates smoothly. If you would like us to check your door while we are in the area, call 020 3725 7665 and we can arrange a convenient time.

Traditional timber front doors — common in the older terraced and semi-detached houses found on roads like Upminster Road South and around Rainham village itself — typically carry two locks: a Yale-type nightlatch near the top of the door, and a five-lever mortice deadlock in the middle or lower section. It is the mortice lock that your insurer is usually asking about when they mention BS3621. A five-lever mortice lock has five internal levers, which makes it considerably more resistant to manipulation than a two- or three-lever version. All BS3621 mortice deadlocks are five-lever, but not all five-lever locks are necessarily BS3621 — the lock must have been independently tested and kite-marked to carry the standard.

If your mortice lock is old, stiff, or simply lacks the kitemark, a lock change Rainham is the practical next step. We remove the existing lock body, fit a new BS3621 five-lever mortice deadlock to the same cut-out where possible (which avoids unnecessary damage to the door), and test the action with the new keys before we leave. If the door frame or keep (the metal plate in the frame that the bolt shoots into) is worn or damaged, we address that at the same time, because a strong lock fitted to a weak keep offers very little real security. The final price we quote covers parts and labour and is confirmed with you before any work starts — the factors that affect the quote include the type of lock required, the condition of the door and frame, and the time of day or day of the week you need the work done.

Start by reading your insurance policy schedule. Look for the section on security requirements or conditions — it will usually specify the type of lock and the standard it must meet for external doors. If the wording refers to BS3621, locate your front door mortice lock, check for the kitemark, and photograph it for your records. If the wording refers to multipoint locks or cylinder standards, check whether your euro cylinder carries a TS007 3-star marking (this is usually printed on the cylinder face or on the packaging if it was recently fitted).

If you cannot find any markings, cannot access the lock body safely, or are simply not confident about what you are looking at, the most sensible step is to have a professional assessment. As your local 24 hour locksmith Rainham, we regularly visit properties where the homeowner just wants a straight answer about whether their locks meet insurer requirements. We carry a range of BS3621 and TS007-rated products on the van, so if an upgrade is needed it can usually be done in the same visit. There is no obligation to proceed — we will tell you exactly what we find and what your options are. To arrange a visit, or if you are locked out Rainham and need help right now, call 020 3725 7665. We answer around the clock, including evenings, weekends, and bank holidays, and we aim to reach you in around 30 minutes.

Before your next renewal, it is worth running through a short checklist. For timber front doors: confirm the mortice lock has a BS3621 kitemark on the lock body; check that the nightlatch is in good working order and that the door closes squarely against the frame; and inspect the keep plate for signs of movement or wear. For uPVC and composite doors: confirm the euro cylinder is TS007 3-star rated and does not protrude excessively beyond the door furniture; check that all multipoint lock hooks and bolts engage cleanly when you lift the handle; and look at whether the frame itself is secure at the hinges and lock side.

If you are a tenant rather than an owner-occupier, you will need your landlord's or letting agent's permission before changing any lock — but you are still entitled to ask your landlord to confirm that the locks meet your insurer's requirements. If your landlord is unresponsive and you have genuine security concerns, our emergency locksmith Rainham service can carry out work and issue a detailed receipt and specification sheet that you can share with both your insurer and your landlord. We work with tenants, homeowners, and managing agents across the Rainham area and understand the different obligations each party has.