Guide
BS 3621, TS 007 and What an Insurance Approved Lock Really Means
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Which Standard Applies to Your Door?
Identify what is installed before matching a standard: the door, its locking component and its inside-opening method decide the route, rather than an insurer assigning a scheme to different hardware. The distinction matters because BS 3621 assesses complete single-point lock assemblies, while TS 007 assesses replaceable cylinders and protective fittings such as security handles.
| Door description | Hardware to identify | Scheme to investigate | Mark or reference | Inspection point |
|---|---|---|---|---|
| Timber door using a recessed lock | Complete mortice assembly | BS 3621 family, where the single-point assembly qualifies | Assembly’s full standard and certification identity | Faceplate, case or manufacturer’s documents |
| Timber door using a surface-mounted lock | Complete nightlatch or rim assembly | BS 3621 family, where the surface-mounted single-point assembly qualifies | Certification attached to that assembly | Body, faceplate or product paperwork |
| Door with a replaceable cylinder, often uPVC or composite | Euro, oval or threaded cylinder; separate protective fittings | TS 007 | Rating and certification for each assessed component | Cylinder, security handle, escutcheon or documents |
| Door allowing departure without an internal key | Key-operated exterior and handle or thumbturn interior | BS 8621 may suit the complete lock assembly | Standard reference for the actual assembly | Lock markings and product documentation |
| Door with normal keyless exit plus a secure setting | Specialist dual-mode assembly | BS 10621 may suit this operating arrangement | Exact assembly’s certification details | Product identification, instructions and certification papers |
For BS 3621, keys operate the lock on both sides. BS 8621 provides outside key operation with keyless release inside; BS 10621 adds the separate secure mode. These are different arrangements, not a ranking of security strength.
Timber construction does not prove BS 3621 certification, and neither uPVC nor composite identifies a rating by itself. Their common euro-cylinder multipoint system needs component-level checks: TS 007 may concern the cylinder and protective handle, but does not rate the entire strip. This guide covers that distinction, TS 007 stars and where markings sit. “Insurance approved” has no formal certification status, and you must check each insurer’s conditions for the particular door alongside building and escape arrangements. A quotation describing a uPVC multipoint lock as BS 3621 suggests the intended component or scheme needs explaining.
Lock Assemblies Are BS 3621, Cylinders Are TS 007
Think of BS 3621 as an assembly assessment and TS 007 as a cylinder-and-protection assessment. They cover different hardware, not competing grades. A euro cylinder sold separately cannot be BS 3621-certified on its own; TS 007 stars cannot be assigned to a lever mortice deadlock. Where both appear in a listing, establish the component behind each claim.
BS 3621: What It Covers and What It Does Not
The current standard reference is BS 3621:2017+A1:2024. Its thief-resistant, mechanically operated single-point assemblies use keys on both sides, with a removable key needed inside. The assessment covers the complete lock’s tested performance.
Qualifying mortice locks and nightlatches fitted to timber entrances are common examples, but both types may lack certification. Check the manufacturer and precise model against the full standard and assembly certification. A count of five levers does not establish BS 3621 compliance.
BS 8621 provides outside key operation with an internal handle or thumbturn; it may apply when the specification calls for keyless exit. Under BS 10621, normal keyless release can be disabled through a separate secure-mode action. Their numbers distinguish operation rather than increasing strength. Confirm escape and building needs before replacing a thumbturn only because insurance paperwork says British Standard.
Who Owns TS 007, and What It Covers
TS 007 includes replaceable oval, threaded and euro-profile cylinders, plus protective handles, cylinder guards, surrounds and escutcheons. Its star-rating options are explained in Door and Hardware Federation guidance.
The cylinder’s rating does not certify a complete multipoint strip, gearbox, door or frame. Protection can carry a separate rating. A new cylinder may suit cylinder damage or an upgrade, but does not resolve a faulty gearbox, failed strip or misaligned door.
| Reference supplied | Corresponding check |
|---|---|
| Complete BS 3621 number and certification marking | Qualifying complete single-point lock assembly |
| TS 007 marking with stars and certification details | Cylinder and any independently rated protection |
Three British Standards, Named for How You Get Out
The difference is the exit method, not which standard has the largest number. These thief-resistant single-point arrangements work as follows:
BS 10621: The Secure Mode
BS 10621 addresses specialist dual-mode lock assemblies for dwellings with an alternative escape route available. It does not denote a stronger BS 8621 arrangement. Suitability rests on the building, intended use and escape provisions, and should be professionally specified. Avoid treating it as a general recommendation for homes, shops or offices. The starting point is the existing internal release.
Keep TS 007 Evidence Component-Specific
TS 007 stars state the security achieved by an assessed cylinder or protective fitting. Their scope does not automatically cover installation, door, frame or multipoint mechanism. The relevant Kitemark should accompany the stars. An advertising claim, including “anti-snap”, cannot establish the rating.
Door and Hardware Federation guidance supports two routes:
- Three-star certification on a TS 007 Kitemarked cylinder, without depending on rated handle protection.
- A TS 007 Kitemarked one-star cylinder used alongside an armoured handle or lock surround Kitemarked to TS 007 at two stars.
The paired products must be recognised together, compatible and correctly installed, with ratings belonging to the fitted parts. Neither an isolated one-star cylinder nor two-star hardware over an unrated cylinder meets that combination. Check the cylinder’s length and profile against the mechanism.
- BS 3621 needs keys on the exterior and interior.
- BS 8621 combines an exterior key with an interior thumbturn or handle.
- BS 10621 has everyday keyless exit and a separately selected secure mode in which internal exit is prevented.
Reaching Three Stars Without Buying a Three-Star Cylinder
You can reach three stars under TS 007 by fitting one TS 007 Kitemarked three-star cylinder, or by combining a TS 007 Kitemarked one-star cylinder with a TS 007 two-star Kitemarked armoured handle or lock surround; the scheme treats either outcome as the same rating.
Three-star cylinder: a single Kitemarked part, rated on its own, with no reliance on a separately rated handle.
One-star cylinder plus two-star hardware: two Kitemarked parts whose ratings only count together.
The combination is recognised because protection does not have to sit inside the cylinder. Someone attacking a door can go for the handle and escutcheon as readily as the cylinder face, so armour around the cylinder does work the cylinder would otherwise have to do itself. The source for both options is the Door and Hardware Federation’s TS 007 page.
Three checks before relying on the combination:
- Kitemarks on both items, each under TS 007, rather than stars printed only in advertising.
- A one-star cylinder underneath, never an unrated one.
- Components that are compatible with each other and properly installed.
Even a correct combination rates the cylinder and its protection, not the multipoint gearbox, strip, door or frame. Put one question to anyone quoting: is this the cylinder route or the combination route, and is each part Kitemarked?
How to Tell What You Already Have
The lock’s visible identification often starts on the door edge, so inspect that before considering replacement.
Describe what is fitted.
Note the material, entrance purpose and general mechanism. A mortice lock sits within the edge; a nightlatch has a visible internal body. BS 3621 covers qualifying complete assemblies, whereas TS 007 covers cylinders and their protective hardware.
Record assembly markings accurately.
With the door already open and controlled, inspect its faceplate or forend and any accessible nightlatch markings. Capture the full number, certification evidence, manufacturer and model. Treat a five-lever stamp as mechanism information.
Check cylinder and furniture independently.
On uPVC or composite doors, inspect accessible cylinder surfaces for TS 007 stars alongside a Kitemark. Look separately at handles and escutcheons. Photograph the cylinder and faceplate, then the handles and whole door, before contacting a qualified locksmith.
Add operation and policy details.
Explain whether inside opening uses a key, handle, thumbturn or separate secure mode. BS 8621 and BS 10621 address distinct inside-opening arrangements. Include the full policy wording; the insurer must confirm compliance with its terms. For a managed building, confirm escape provisions before changing inside release.
Note: Unseen markings do not mean a lock failed testing or is unsuitable. Documentation may identify it, but unsupported certification should remain unclaimed. Leave parts assembled; inspection or exact measurements may be needed for model and compatibility checks. A locksmith can discuss repair or replacement, while product certification alone cannot establish whole-door insurance or building compliance.
What Insurance Approved Actually Means
No organisation approves locks for insurance. BSI certifies a product against a published standard, and each insurer decides separately what its own policies ask for. “Insurance approved” is trade shorthand for a lock certified to a standard that insurers commonly name, and it is not a certification in itself. Some policies specify BS 3621 for certain external doors, and requirements vary by insurer, door type and policy. A certified lock does not automatically satisfy every policy, so before relying on the phrase, check which standard or rating the exact product carries and what your own policy says about that door.
Who Certifies What
These four ideas are linked but not interchangeable:
- Security standard: sets the technical requirements and test methods for one type of lock or component.
- Product certification: shows that an identified product has been assessed under a stated scheme.
- Product marking: Displays information such as a BS number, Kitemark or TS 007 star rating.
- Policy condition: states what an insurer expects for a particular property, door or situation.
For example, a mortice lock may carry BS 3621 certification. It provides information about the lock assembly that underwent testing. It does not prove that every insurer will accept it for every entrance. A TS 007 rating works in the same way: it is evidence about the cylinder or protective hardware carrying it, not confirmation that the whole door meets an insurance condition. A BS 3621-family marking relates to a qualifying complete lock assembly. A TS 007 rating normally relates to the cylinder or separate protective hardware.
Your Own Policy: What to Check
When a seller or installer calls something “insurance approved”, ask which standard it carries, which component the marking is on, and whether you can see it. Then compare that with the exact words in your policy. Record the full number rather than writing only “British Standard.” Different standards describe different inside-opening arrangements. A five-lever marking does not prove BS 3621 certification, because lever count and a standard reference tell you different things.
Worth noting down from the lock itself:
- The complete BS number, if one is shown
- A TS 007 reference
- A Kitemark or other relevant certification marking
- The manufacturer and model reference
If you photograph the lock for your records, frame the whole door first, then close-ups of the faceplate, the cylinder and the Kitemark or TS 007 stars. Do not change the inside-opening method without checking whether the door forms part of an escape route or managed building. A locksmith can identify the hardware and explain what its markings mean, but only the insurer can confirm how a policy condition applies to your property, and the same holds if you are securing a property after a break-in.
PAS 24 assesses the enhanced security performance of a complete doorset; BS 8621 is not automatically the applicable standard for every flat entrance door.
Talk with Us About What Your Door Takes
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British Standard Lock Questions
Does a five-lever lock automatically meet BS 3621?
No. For a policy or specification requiring BS 3621, the exact model needs checking. A five-lever label does not verify compliance: it refers to internal levers that the key must position before the bolt moves. BS 3621 covers performance testing of the complete assembly, which must meet those requirements and bear verifiable certification markings. Five-lever models may differ in construction and security features. Even comparison with a basic three-lever design, a familiar brand or the key, bolt and faceplate provides no substitute for verification.
Does BS 3621 apply to locks on uPVC doors?
The usual cylinder-operated multipoint setup on a uPVC door does not generally come under BS 3621. TS 007 may instead be relevant at component level, covering the replaceable cylinder and associated protective hardware. Keep that distinction in mind when checking markings: certification under it excludes the complete door and multipoint mechanism.
Is a three-star cylinder the only way to achieve the TS 007 three-star security level?
There are two recognised routes, so the answer is no. A TS 007 combination can use protective hardware carrying two stars alongside a cylinder carrying one star; each must bear the TS 007 Kitemark. The alternative is a three-star cylinder certified with that Kitemark under TS 007.
Is an anti-snap lock the same as a TS 007 three-star cylinder?
No, anti-snap wording is insufficient evidence of certification. A cylinder's three-star status under TS 007 needs checking through the Kitemark and its star count. The product's name does not establish that rating, and relying only on packaging language leaves the same question unanswered.
What does it mean if my lock has no visible Kitemark?
An unseen Kitemark does not, by itself, establish that the lock is unsuitable or has failed testing. Check other product surfaces, the packaging and original documents. Photographs and a product reference may help identification without dismantling. Certification needs a verifiable standard and marking, not assumptions based on appearance, brand, key shape, lever count or a seller's description. An unverified 'insurance approved' claim is insufficient too. If the marking remains unconfirmed, record the lock as unidentified rather than certified.
Will changing the cylinder make my entire door compliant?
No. Replacing a cylinder updates a single component, so it cannot establish compliance for the entire entrance. It provides no certification for the handles, multipoint mechanism, frame, door or fitting work. If insurance, building or security requirements apply, an assessment of the complete entrance may be needed.
Is PAS 24 the same as BS 3621 or TS 007?
No, complete doorsets and locking components are assessed under different specifications. PAS 24 covers enhanced security performance for the entire doorset. BS 3621 is for qualifying single-point lock assemblies. Replaceable cylinders, along with their related protective hardware, come within the scope of TS 007 instead.
Does a British Standard lock automatically satisfy my home insurance policy?
No. Meeting a British Standard does not establish that a lock satisfies every home insurance policy. The insurer, the particular policy and the entrance concerned can affect the requirements. Read the policy in full and seek written clarification if it leaves the required standard unclear.
Does every flat entrance door need a BS 8621 lock?
The requirement is not automatically the same for every flat entrance. BS 8621 applies to qualifying assemblies that lock at one point and allow someone inside to leave without a key. What is appropriate depends on the complete doorset and applicable building, fire and property-management requirements.
Where can I find the BS 3621 or TS 007 marking?
The location varies with the manufacturer and lock design. Look for BS 3621 details in the documentation, on the packaging, or on the case and faceplate. TS 007 markings may be carried by the cylinder or protective hardware. A star count needs checking alongside the certification mark and the number identifying the standard.