What Types of Door Locks Do I Need For Insurance?

Most home insurers in the UK require your door locks to meet specific standards, and if they don’t, you could find a claim rejected, even one that has nothing to do with a break-in. The BS3621 British Standard is the benchmark most insurers use. Here’s what that means in practice and which locks you need for each part of your home.

Why door locks matter for home insurance

Insurers assess the security of your home as part of their risk calculation. Inadequate locks increase the chance of a successful break-in, which increases the likelihood of a claim. If your locks fall below the standard specified in your policy, your insurer may:

• Reject a theft claim on the grounds that the property wasn’t adequately secured
• Void the policy entirely in some circumstances
• Charge a higher premium to reflect the increased risk

This applies even if the claim itself isn’t related to the door lock. It’s a condition of cover, not just a recommendation.

According to the Office for National Statistics (ONS), most residential burglaries involve entry through doors or windows. Proper locks are your first line of defence.

What is BS3621?

BS3621 is a British Standard certification for locks that have passed rigorous testing for resistance to common break-in methods, including picking, drilling, and snapping. A BS3621 certified lock will display a kitemark either on the lock itself or in the product documentation.

These locks are designed to meet the security expectations of UK insurers. If your policy requires BS3621 compliance, fitting a lock with the kitemark is the safest way to ensure you meet the standard.

Types of door locks and whether they meet insurance requirements

Here’s a closer look at the most common lock types and where they stand with insurers:

Types of door locks and insurance requirements

Lock type	Insurance status	Best for
Five-lever mortice deadlock (BS3621)	Widely accepted as standard	Front doors
Night latch (Yale lock)	Not sufficient alone	Needs to be paired with a deadlock
Euro cylinder lock (anti-snap, anti-pick, anti-drill)	Accepted if high-security spec	Composite and uPVC doors
Multipoint locking system (BS3621 or PAS 24)	Accepted for appropriate door types	Back doors, patio doors, uPVC doors
Padlock (BS3621 or equivalent)	Accepted for outbuildings and garages	Sheds, garages, gates
Smart lock	Accepted by some insurers only	Check your policy

Front door requirements

For front doors, most insurers insist on a five-lever mortice deadlock that complies with BS3621. This type of lock is morticed into the door itself, making it significantly harder to force than a surface-mounted lock.

A night latch, commonly known as a Yale lock, is not sufficient on its own. It provides convenience but doesn’t meet BS3621 requirements. Combining a night latch with a BS3621 mortice deadlock provides the security level most insurers require.

For example:

A homeowner is burgled through their front door. The door had only a night latch fitted. Their insurer rejects the theft claim on the grounds that the door didn’t meet the policy’s lock requirements. A £200 deadlock would have kept the claim valid.

Back door and patio door requirements

Back doors and windows are common entry points for burglars and are treated differently by insurers.

• Back doors (composite or timber). A BS3621 compliant lock is required, typically a mortice deadlock or multipoint system.
• uPVC and composite doors. Multipoint locking systems are the standard. These engage multiple bolts along the full height of the door frame, making forced entry significantly harder. Look for PAS 24 compliance as well as BS3621.
• French and patio sliding doors. Multipoint locking is usually required, plus anti-lift devices to prevent doors being pried out of their tracks.

Smart locks and whether insurers accept them

Smart locks are increasingly popular, particularly for their integration with smart home automation systems. However, not all insurers accept them as equivalent to traditional BS3621 locks.

If you want to use a smart lock, check:

• Whether your insurer specifically approves the model or type
• Whether it meets BS3621 or an equivalent standard
• Whether it has a manual override in case of power or connectivity failure
• Whether your policy requires any additional security features alongside it

Some insurers will accept smart locks that meet BS3621 standards and have strong physical security features. Others may require a traditional BS3621 lock to remain in place alongside the smart lock. Always confirm with your insurer before making the switch.

What to do if your locks don’t meet requirements

If you’re not sure whether your locks meet your insurer’s standards, start with your policy documents. These should set out exactly what’s required. If anything is unclear, call your insurer and ask directly.

If your locks do fall short:

1. Identify which doors need upgrading. Front doors, back doors, and patio doors are the priority.
2. Get quotes from a qualified locksmith. Look for locksmiths registered with the Master Locksmiths Association (MLA), who can advise on and fit compliant locks.
3. Upgrade before you need to make a claim. Don’t wait for an incident to discover your cover is invalid.
4. Notify your insurer. Once the locks are upgraded, let your insurer know. It may also reduce your premium.

Before we go

Your door locks directly affect the validity of your home insurance. Fitting BS3621 compliant locks on front doors, back doors, and patio doors is the most reliable way to meet standard insurer requirements and protect your home. Check your policy wording, upgrade if needed, and confirm with your insurer if you’re unsure.

Lemonade’s home insurance is designed to be clear about security requirements, so you always know exactly what’s expected.

Door locks for insurance FAQs