Mortice Lock Replacement (BS3621) — 5-Lever

BS3621 mortice lock supplied and fitted from £95. The 5-lever mortice deadlock is the gold standard for wooden doors and the minimum specification required by most UK home insurance policies. We supply Kitemarked BS3621 locks from Chubb, Union and ERA.

What's included

• Removal of the existing mortice lock
• Supply of a Kitemarked BS3621 5-lever lock
• Chiselling or adjustment of the mortice pocket if required
• Two new keys
• Strike plate fitting and function test

Pricing

Standard BS3621 5-lever lock from £95. Premium hardened versions (with anti-drill plates and hardened bolts) from £135. Both grades meet UK insurance requirements. No VAT and no call-out fee — the price you see is the price you pay. Parts and labour are included unless otherwise stated.

Frequently asked questions

How do I tell if my current lock is BS3621?
Look for a kitemark (a heart-shaped symbol) stamped on the faceplate of the lock. No kitemark = not BS3621.

Is a sashlock or deadlock better?
It depends on the door. Deadlocks pair with a separate night latch; sashlocks combine deadbolt and latch in one. We advise on the day.

What if my door is too thin for a BS3621 lock?
BS3621 locks require a minimum door thickness of 44mm. If your door is thinner we'll recommend an alternative approved solution.

Service area & guarantee

We serve Preston, Lancashire and the surrounding PR postcode area. Same-day and emergency appointments available. All work is carried out by a fully insured local locksmith — no national call-centre middlemen. All our work is backed by a 12-month workmanship guarantee.

Book online by selecting your option and adding to cart, or call us on 07786 917834 for advice and emergency callouts.