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Window lock buying guide

Updated: 16 October 2026

You already have a handle on a uPVC casement, and the next packet on amazon.co.uk says window lock. That word covers a cable that lets the sash travel a short way, a timber latch that pulls the sash shut, and a hook whose listing tells you to leave it off double-glazed UK windows. This window lock buying guide puts the job, the frame, the fixing and the key ahead of the price. The nine listings, captured on 15 October 2026, are on the [window lock comparison](/hub/burglar-protection/window-lock). If you buy through our links, we may earn a commission at no extra cost to you. The page is from the Products Compared editorial team.

You already have a handle on a uPVC casement, and the next packet on amazon.co.uk says window lock.

Our top picks

Schlosser Technik Schlosser Technik cable restrictor, 2 pack

Best overall

Schlosser Technik Schlosser Technik cable restrictor, 2 pack
8.6/10about £13.40
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XFORT XFORT Viper cable restrictor, 4 pack

Preis-Tipp

XFORT XFORT Viper cable restrictor, 4 pack
8.3/10about £18.99
View offer
Yale Yale 8K101 window latch, 4 pack

Alternative

Yale Yale 8K101 window latch, 4 pack
8.4/10about £20.98
View offer
On this page
  1. 1.Shut and locked, or a limited opening
  2. 2.Match the device to the frame
  3. 3.Screws, keys and the gap you will actually get
  4. 4.What to ignore on the packet

Shut and locked, or a limited opening

A keyed cable limits travel until you release one end. While it is on, the sash is ajar, not shut. An empty house needs the sash closed, on a lock whose key comes out. A cable left on an open sash does not do that. Most uPVC casements already lock through the espag handle, so these products are a second device. A little air upstairs means a limiter. A hinged timber casement with no multi-point handle means a shut-lock. AXA Connect LC01 is one insurance example: key-operated locks with detachable keys on accessible windows when the home is empty. If the timber sash must be shut and keyed, go to window restrictor vs window lock.

Match the device to the frame

On uPVC, aluminium and many PVC casements, the usual retrofit is a keyed cable. The screw-fixed ones are the XFORT Viper four-pack, the Schlosser Technik two-pack and the eSynic set. Adhesive-or-screw multipacks are cheaper, and several pages also say fridge or cupboard. Hinged timber, including a fanlight, is where the Yale 8K101 belongs. It has no cable and is not described for uPVC. The stainless hook is the other miss: the listing says it is not for double-glazed UK windows, it lists no key, and amazon.co.uk shows 5.0 from one review. Who should skip which listing is on the best window lock page.
Schlosser Technik Schlosser Technik cable restrictor, 2 pack

Testsieger

Schlosser Technik Schlosser Technik cable restrictor, 2 pack
8.6/10about £13.40
View offer

Screws, keys and the gap you will actually get

Screw into sound material wherever a fall would injure someone. Adhesive is secondary. Stored UK reviews on the shared packs say pads were pulled off, including by a strong child, and that screws held. If you rent and must not drill, ask the landlord first. The key has to leave the lock and stay where an adult can find it at night if the window is an escape route. Stored Schlosser reviews describe one key per lock. The Yale box is four latches and a key. Measure along the whole sash, not only beside the cable. One restrictor by the handle can leave a larger gap at the far end. Printed travel is 188 mm on the shared packs and 19 cm on eSynic. XFORT and Schlosser do not print a length. Approved Document K paragraph 8.2 does not set 100 mm for every home.

What to ignore on the packet

Ignore a standard with no number. Schlosser's title says tested to British Standards and names nothing. That is not BS EN 13126-5, PAS 24 or Secured by Design. A screw-on cable is not a test of a complete new-dwelling window. Ignore a review count doing three jobs. The £5.99 two-pack, the £11.99 four-pack and the MIVITOOM eight-pack at £19.94 share 4.5 from 1,587 and the same first 50 stored UK texts. The four-pack first listed on 18 August 2026 has no star line. Call a joiner, a locksmith or the landlord if the frame is rotten, the escape route is unclear, or someone has named PAS 24 or a specific lock.

Common questions

Does a uPVC window that already locks on the handle need another lock?
Often it does not, if the espag handle still throws the bolts and you will leave the sash shut. Add a second device when you want a limited opening, or when your schedule asks for a key-operated lock on an accessible window and the handle does not meet that wording. A cable on an open sash is not a shut window. If the bolts miss the keeps, repair the handle first.
Is a cable restrictor the same as a window lock?
Shops file both under window lock. A keyed cable keeps the sash partly open until you release it. The Yale 8K101 clenches a hinged timber casement shut. Closed while you are out means the latch, or the handle you already have. Air with a limited gap means the cable.
Are adhesive pads enough?
Only as a secondary fixing on a clean, flat face. Stored reviews on the shared packs say pads were pulled off, including by a strong child, and that screws held. Where a fall would injure someone, screw the plates. Renters who may not drill need the landlord's consent.
Will any keyed gadget satisfy home insurance?
No. AXA Connect LC01 is one example: detachable keys on accessible windows when the home is empty, keys out of sight, and keys left in at night only on the escape route. Your schedule may differ. A cable on an open sash does not match a shut window, and none of these listings is insurance-approved or Secured by Design.
What does tested to British Standards mean with no number?
The title claimed a test and did not name it. Schlosser's listing does this. You cannot read it as BS EN 13126-5 or PAS 24. A standard counts here only when the identifier is printed. BS 3621 is a door-lock standard in the AXA example, not a window requirement for these cables.
What should a renter do if drilling is not allowed?
Ask the landlord before you drill. An adhesive pad is not a substitute on a window where a child could fall, and pads failed in stored reviews when they were the only fixing.

Related pages

Window restrictor child safety

Window locks

Best window lock: which listing matches your frame

Window restrictor vs window lock: use cable or latch

How to fit a window restrictor on uPVC or on timber

Sources

Public UK sources and the amazon.co.uk listings in this comparison. Listings captured 15 October 2026. Page updated 16 October 2026.

  1. Approved Document K (2013) (retrieved 15 October 2026)
  2. Approved Document Q (retrieved 15 October 2026)
  3. HSE: falls from windows (retrieved 15 October 2026)
  4. CWCT: are window restrictors designed to resist adequate loads (retrieved 15 October 2026)
  5. BSI: PAS 24:2022+A1:2024 (retrieved 15 October 2026)
  6. AXA Connect LC01 locks requirement (retrieved 15 October 2026)
  7. MLA minimum security requirements, January 2025 (retrieved 15 October 2026)
  8. RoSPA: falls (retrieved 15 October 2026)