Lock Change, Lock Repair & Replacement in London
Lock Repair and Lock Change Jobs We Do Every Week
Stiff or Sticking Locks
A key that only turns with force, or a bolt that drags. Usually worn pins, dirt or a dropped door. We service or replace the lock before the key snaps.
Fix It Before It FailsLost, Stolen or Copied Keys
If you do not know who has a key, you do not control your front door. We change the cylinder or lock and test the new keys on the door.
RekeyingMortice Lock Replacement
Most timber front doors use a five-lever mortice deadlock. We fit BS 3621 locks, which many insurers ask for, matched to your existing lock size where possible.
BS 3621 Mortice LocksEuro Cylinder Upgrades
Ordinary cylinders can be snapped by burglars. We measure your door and fit a TS007 3-star cylinder that resists snapping, bumping, drilling and picking.
TS007 3-Star CylindersNightlatches and Rim Locks
Loose, worn or damaged latches on front doors and flat doors. We repair or replace the lock, keep and cylinder, then check the door closes properly.
Repair or ReplaceNew Tenants and Changeovers
A lock change between tenancies puts you back in control of who holds keys. We supply the right number of keys for everyone.
Move-In SecurityLock Replacement in London, or a Simple Repair?
BS 3621 Locks and What Your Insurer Expects
Fitted to Your Policy
Policies often ask for a five-lever BS 3621 lock on timber doors. We check your door and recommend what will meet the standard.
Finishes and Keys That Match
Brass, chrome or black to suit your door furniture, with keyed-alike options so one key opens front and back.
12-Month Workmanship Guarantee
Locks and fitting are covered for 12 months, with a written note of exactly what was fitted.
Check, Quote, Fit and Test
Tell Us About the Lock
The door type, what the lock is doing and any markings on the faceplate. A photo helps us bring the right parts.
Photos help us prepareWe Check and Quote
We inspect the lock, door and keep, explain whether repair or replacement is better and confirm a written price.
Both options pricedWe Fit and Test
The work is done neatly, the lock tested with you from both sides, and spare keys handed over with guarantee details.
Tested with you before we goHow Much Does It Cost to Change Locks on a House?
For stiff, loose or worn locks that can be restored rather than replaced.
- Lock and keep checked
- Cleaned, lubricated and adjusted
- Handle, strike or keep repaired
- Tested from both sides
For lost keys, worn locks or an upgrade to a recognised security standard.
- Cylinder measured and replaced
- BS 3621 / TS007 options
- New keys supplied and tested
- Old lock taken away
For landlords, new homeowners and businesses with several locks.
- Every outside door checked
- Keyed-alike options
- Key list for tenants or staff
- 12-month workmanship guarantee
Written Price Before Work
Our price covers your area with no congestion charge, parking or travel extras.
Lock Change FAQs
How much does it cost to change the locks on a house?
A 2026 price guide puts a London lock change at about £120 to £230, a Euro cylinder change at £90 to £180 and a BS 3621 mortice lock at £140 to £260 in normal hours (BestBuilders). The total depends on how many doors you have. We quote in writing before starting.
Do I need a BS 3621 lock for my home insurance?
Many home insurance policies ask for a five-lever BS 3621 mortice lock on external timber doors, and a claim can be refused if the required lock was not fitted. Check the security section of your policy. We fit BS 3621 locks and can tell you whether your current lock meets the standard.
What is a Euro cylinder replacement?
A Euro cylinder is the barrel your key goes into on most uPVC, composite and many timber doors. Replacing it changes which key works, so it is a quick way to lock out old keys. We measure it precisely and can fit a TS007 3-star anti-snap cylinder at the same time.
Should I repair my lock or replace it?
It depends on its condition. A stiff lock caused by dirt or a dropped door can often be restored. A worn, damaged or outdated lock, or one below your insurer’s standard, is better replaced. We explain both options and quote them so you can decide.
What is a TS007 3-star cylinder?
TS007 is a standard for Euro cylinders. A 3-star cylinder meets the top rating on its own, resisting snapping, bumping, drilling and picking. It is a sensible upgrade on any uPVC or composite door that still has a standard cylinder fitted.
Do I need to change the locks when I move in?
It is strongly advised. You cannot know who holds copies of the old keys, such as previous owners, tenants or builders. Changing or re-keying the external locks means only you control who gets in. We can usually do every door in one visit.
Can you supply extra keys or keyed-alike locks?
Yes. We supply extra keys with new cylinders and can fit keyed-alike sets, so one key opens both the front and back doors. Restricted keys that cannot be copied without your permission are also available if you want tighter control.
Repair, Cylinder or New Lock?
Not sure whether your lock needs a repair, a new cylinder or a full replacement? Call us for honest, practical advice.
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