Window Locks

SS Window Lock, from our current range.

What is a window lock?

A window lock is a key-operated fitting that secures a window in its closed, or sometimes partially open, position, preventing it from being opened from outside. It can take the form of a dedicated standalone lock, a locking casement fastener, or a locking window stay, but all serve the same purpose of adding key-controlled security beyond a window's standard fastening. Window locks are frequently specified alongside door locks to meet UK home insurance requirements.

Many insurers expect accessible ground and first floor windows to be lockable, so it is worth checking your policy's specific requirements before choosing hardware.

Where window locks are used

• Ground and accessible floor windows – the most important windows to secure, often specifically required by insurers
• Rental and let properties – landlords frequently fit window locks as standard across a property
• Alongside window stays – locking stays combine ventilation control with security in one fitting

Choosing the right window lock

A few practical points are worth checking before you buy:

• Window type – casement, sash and other window types each use different lock styles; check compatibility with your window
• Keyed alike – useful where several windows in a property should share the same key
• Insurance requirements – check your policy's specific wording on window security before buying
• Coordination with other hardware – see our Window Furniture Guide for related casement and stay hardware

Related products

Browse Window Locks via search, or see the related Window Furniture Guide.

Frequently asked questions

Do I need window locks for insurance?

Many UK home insurance policies specify that accessible windows, typically ground floor and easily reachable upper floor windows, must be lockable. Check your policy wording to confirm.

Can window locks be fitted to any window?

Most casement and sash windows can accept a suitable window lock, but the specific type needed depends on the window's construction, so it is worth checking compatibility before ordering.

Can window locks be keyed alike with my door locks?

Some ranges offer keyed alike options across their window and door lock products; check with us if you would like every lock on a property to share one key.

Back to the Locks & Security Guide, or explore the full Knowledge Centre.