Door Locks UK: The Complete Guide to Choosing the Right Lock

Door locks are the first — and most important — line of defence against break-ins, yet most UK homes have locks that are at least ten years out of date. Choosing the right door lock in the UK means understanding a handful of British Standards, knowing which cylinder grades actually resist modern attack methods, and recognising that the lock is only as strong as the door and frame it’s fitted to. This guide covers everything: lock types, standards, anti-snap and anti-bump cylinders, fitting costs, and what a secure front door actually looks like in 2026.

UK Door Lock Types: Which One Do You Have?

Understanding your existing lock type is the starting point for any upgrade decision.

Yale Nightlatch

The Yale-style nightlatch is the most common lock in UK homes — the spring-loaded bolt you pull the door closed on without needing a key from the inside. On its own, it offers very limited security. A standard nightlatch can often be slipped with a credit card and provides no resistance to being forced. Always used in combination with a deadlock; never as the sole lock on an external door.

Deadbolt

A deadbolt (or deadlock) throws a solid steel bolt into the frame that cannot be pushed back without turning the key. Deadbolts meeting BS3621 are a common insurance requirement. They come in sash lock form (with a separate latch above the deadbolt, operated by a handle) or as standalone deadlocks. These are the locks that actually stop a door being forced.

Multipoint Locking System

Most modern uPVC and composite doors use a multipoint lock — a single handle operation that simultaneously throws hooks, bolts, or rollers at three or more points up and down the door frame. These are significantly stronger than a single deadbolt because forcing the door requires defeating the entire frame at multiple points. The cylinder (the barrel you insert your key into) is still the weak point.

Mortice Lock

A mortice lock is set into a pocket (mortice) cut into the door edge. Five-lever mortice locks meeting BS3621 are the gold standard for wooden doors and are required by most UK insurers on front and back doors. A two-lever mortice lock offers very little security and should be replaced.

BS3621: The Standard Your Insurer Cares About

BS3621 is the British Standard for Thief Resistant Locks. It defines the minimum performance requirements for locks on external doors in the UK, covering resistance to picking, drilling, and forcing. If your home insurance policy specifies a BS3621 lock — and most do — and you make a claim after a break-in where the lock doesn’t meet the standard, your claim may be refused.

Locks bearing BS3621 certification will have the kitemark and the number stamped on the faceplate or in the product documentation. If in doubt, check your insurer’s policy schedule — the lock requirement is usually listed in the security conditions section. Which? has a useful overview of lock standards if you want to verify what meets the threshold.

PAS 24 and Secured by Design (SBD)

PAS 24 is the enhanced security specification for doorsets — meaning the entire door assembly (door, frame, glazing, hardware) rather than just the lock. It’s the standard required on new-build homes under Part Q of the Building Regulations in England. If you’re buying a new door, look for PAS 24 certification: it means the complete assembly has been tested against forced entry, not just the lock in isolation.

Secured by Design (SBD) is a police-backed scheme that certifies products and developments meeting enhanced security standards. Products bearing the SBD mark have been independently tested. You can search for approved products on the Secured by Design website. SBD certification is often required for social housing and new developments, but it’s a useful quality indicator for any buyer.

Cylinder Grades: TS007 and Anti-Snap Protection

The cylinder is the most attacked part of a modern door lock. Cylinder snapping — where a burglar breaks off the outer part of the cylinder with a hammer, exposing the inner mechanism and allowing the door to be opened — is now one of the most common break-in methods in the UK, particularly on uPVC doors with multipoint locks.

TS007 is the British Standard for cylinders, with three grades:

For almost all UK homes with uPVC or composite doors, upgrading to a TS007 3-star cylinder (or a 2-star cylinder plus 1-star handle furniture) is one of the highest-impact security upgrades you can make, at relatively low cost. Brands such as Yale, Brisant Ultion, Avocet ABS, and ERA offer well-reviewed 3-star cylinders in the £40–£80 range.

Also look for cylinders that resist:

• Bumping: Where a specially cut key is tapped into the cylinder to set the pins and turn it.
• Picking: Manipulating the pins with lock picks — rarer in residential burglary but relevant for higher-risk properties.
• Drilling: Destroying the cylinder with a drill. Anti-drill pins (hardened steel pins inside the cylinder) resist this.

How Much Does a New Door Lock Cost in the UK?

Swapping a cylinder on a uPVC door is something a confident DIYer can do in 10 minutes with a screwdriver, and is one of the easiest security upgrades there is. Mortice lock replacement on a wooden door requires more skill and tools — a locksmith is the safer option. See our guide to window and door security for additional measures beyond the lock itself.

Beyond the Lock: What Actually Makes a Door Secure

A high-grade cylinder fitted into a weak door frame provides almost no protection. The door itself, the frame, the hinges, and the way it’s fitted all matter as much as the lock. Check these:

• Door frame: The frame should be solidly fixed to the masonry, not just the plasterboard. Strike plates — the metal plate the bolt enters — should be secured with screws at least 75mm long to reach the structural frame behind.
• Door hinges: External door hinges should have hinge bolts (dog bolts) fitted on the hinge side to prevent the door being lifted off if hinges are attacked.
• Door letterbox: A letterbox cage or restrictor on the inside prevents someone fishing for keys or reaching the handle. Letterboxes should ideally not be positioned within arm’s reach of the lock.
• Glazing: Doors with glass panels near the lock can be broken to reach through and operate the lock. Laminated or toughened glass and double-cylinder locks (requiring a key from both sides) address this — though double-cylinder locks require care for fire escape purposes.
• Door viewer: A wide-angle door viewer (peephole) reduces the need to open the door to unknown callers.

For a comprehensive view of home security beyond just locks, our guide to how to secure your home in the UK covers the full picture, and our smart locks review is worth reading if you’re considering keypad or app-controlled access. The Metropolitan Police’s door security advice is also a practical resource.