Lock Installation Cost & Work Guide

Whether you have recently moved into a new property, suffered a lockout, or simply want to upgrade to "anti-snap" technology, a professional locksmith ensures the job is done without damaging your door frame or compromising your warranty. This guide breaks down the essential costs and considerations for lock installations in the UK.

What Does the Work Involve?

• Security Assessment: The locksmith inspects the door material (uPVC, timber, or composite) and checks for British Standard (BS3621) compliance.
• Site Preparation: Removing existing hardware and measuring the backset and centres to ensure the new lock fits perfectly.
• Door Modification: For "fresh fits" (new installations), this involves chiselling out a mortice or drilling new holes for cylinders and handles.
• Component Fitting: Installing the internal mechanism, the external cylinder or lever, and the strike plate on the door frame.
• Alignment & Testing: Adjusting the strike plate to ensure the bolt throws smoothly without needing to pull or push the door.
• Key Handover: Testing all provided keys (usually 2 or 3) and explaining any specific maintenance or smart features.

Typical Costs

Prices vary significantly based on the type of lock and whether the locksmith is attending a scheduled appointment or an emergency out-of-hours call. All prices below include estimated parts and labour for 2025/26.

Labour rates are generally higher in London and the South East. Most locksmiths charge a fixed price for the first hour and then increments of 30 minutes thereafter.

How Long Does It Take?

• Cylinder Swap (uPVC/Composite): 20–40 minutes. Usually a straightforward "like-for-like" replacement.
• Mortice Lock Replacement: 45–90 minutes. May require minor wood adjustments to the door or frame.
• Fresh Fit (New Hole): 1.5–2.5 hours. Requires precision drilling and chiselling into a door that previously had no lock.
• Smart Lock Integration: 1–2 hours. Includes physical fitting and syncing with mobile apps or hubs.

DIY or Professional?

While swapping a basic Euro cylinder is a common DIY task, it carries risks. If you measure incorrectly and the cylinder protrudes more than 3mm from the handle, it becomes an easy target for "lock snapping." For timber doors requiring mortice locks, a professional is recommended to avoid splitting the wood. Furthermore, most UK insurance providers stipulate that locks must be fitted to BS3621 standards by a competent person to remain valid.

Choosing the Right Tradesperson

• Check Credentials: Look for members of the Master Locksmiths Association (MLA), as they are vetted and inspected.
• DBS Checked: Ensure the locksmith has a clean, recent Basic DBS check for your peace of mind.
• Avoid "National" Call Centres: Try to book a local independent locksmith to avoid inflated commission-based pricing.
• Questions to Ask:
  • Are the locks you're fitting BS3621 compliant?
  • Does the price quoted include VAT and the call-out fee?
  • Do you offer a guarantee on both the part and the labour?

UK Regulations

• BS3621: The British Standard for thief-resistant locks. Look for the "Kitemark" on the faceplate of the lock.
• TS007: The standard for cylinders. A "3-star" rating (either a 3-star cylinder or a 1-star cylinder with 2-star handles) is the gold standard for uPVC doors.
• Fire Safety: For flats or HMOs, locks must often allow "keyless egress" (thumb-turns) to ensure residents can exit quickly in a fire without searching for a key.

Pro Tip: Always check your home insurance policy "Key Facts" document. Many insurers will void a burglary claim if your locks do not meet the 5-lever British Standard or TS007 3-star requirement.

Common Problems

• Misaligned Striker Plates: If you have to "heave" the door to lock it, the lock will eventually fail. A pro will align the frame perfectly.
• Cheap Imports: Non-branded locks found online often lack the hardened steel plates required to resist drilling.
• Wrong Cylinder Size: Using a cylinder that is too long makes it vulnerable to snapping; one that is too short makes it difficult to operate.
• Over-tightening: Tightening fixing screws too hard on uPVC doors can pinch the internal gearbox, leading to an expensive mechanism failure.

Frequently Asked Questions

What is "Lock Snapping" and how do I prevent it?

Lock snapping is a method used by burglars to snap a Euro cylinder at its weakest point (the screw hole). You can prevent this by installing a TS007 3-star rated cylinder or an SS312 Diamond rated lock, which are designed to snap in a way that keeps the central cam secure.

Do I need to change my locks when I move into a new house?

Yes, it is highly recommended. You have no way of knowing how many spare keys were given to neighbours, tradespeople, or previous tenants. Changing the locks ensures you are the only person with access.

What does a "5-lever" lock mean?

This refers to the number of internal levers the key must move to open the lock. A 5-lever mortice lock is more secure than a 2 or 3-lever version and is the minimum standard required by most UK insurers for external timber doors.

Can I have one key for all my doors?

Yes, this is called "Keyed Alike." A locksmith can pin multiple cylinders so they all operate with the same key, reducing the bulk on your keychain. This works best for doors of the same type (e.g., all uPVC or all timber).

Will a locksmith damage my door if I'm locked out?

A professional locksmith will always aim for "non-destructive entry" using picking or bypassing tools. Drilling the lock is usually a last resort and should only result in needing a new lock, not a new door.