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Home > ADVICE AND TIPS (FAQS) > What are BS3621 Locks? + How to tell you have British Standard Locks
Find out what BS3621 locks are, and how to tell in 2 easy steps you have BS3621 British Standard locks fitted on your doors. We will also tell you the advantages of having your door locks conform to BS3621.
BS3621 is a lock standard by British Standards Institute (BSI) for thief-resistant locks, BS-3621 locks are found on some front and back doors in the home and it’s a good way to check that your security is up to standard. This is why some insurance companies require door locks are fitted to BS 3621 British Standard.
The first question you will want to know is do my current door locks already conform to BS3621?
One way to check your front or back door locks are conforming to BS3621 is to look for the British Standard Kitemark (BSI) on the faceplate of the lock. The faceplate of the lock is viewable when you open the door; you should also see the specific standard number e.g. BS3621 stamped on the plate.
What the BS3621 Kitemark looks like
If you are unsure ask a local MLA approved locksmith in your area who deals with these type of locks every day, they will also be able to upgrade your current locks to BS 3621.
BS 3621 is the original lock standard and was first introduced in the 1960’s, the key facts you need to know about BS3621 locks are as follows:
Not Suitable For – This standard of lock makes it unsuitable for properties with only one exit door.
The main benefits of having BS3621 British Standard approved locks fitted are:
You may see Kitemarked BS3621 locks referred to as “Insurance Approved Locks”, this just means some insurance companies require this standard of lock fitted.
BS-3621 locks are NOT actually approved by Insurance providers, the approval and certification is done by BSI (The British Standards Institute) themselves.
You will find the following types of door locks that conform to BS-3621 in your home.
For mortice locks to conform to BS3621 the door lock must have at least 5 levers, therefore a 3 lever mortice lock CANNOT be British Standard Kitemarked to BS3621.
Confused about what door lock you have? Please read our door lock types guide here. which also includes pro’s and cons of each lock.
The below photo shows what a Mortice Deadlock that is BS3621 approved locks like, note the Kitemark with the standard number below it found on the lock.
Please note that some 5 lever mortice lock DO NOT conform to BS3621, so please check before you purchase or ask a local MLA locksmith.
For a lock to meet British Standard BS3621 it must have:
Over the years the BS3621 standard has been updated leading to there being different versions of BS 3621 locks available, the different years indicate the date of the standard it was approved to.
Below is a list of versions your lock could be:
NOTE: The year of lock certification is not as important as actually having a BS3621 lock fitted, although it is recommended to upgrade to the latest version.
Some insurers may insist your locks have to meet BS3621, other insurers may not have that exact requirement, so it’s down the individual to check with their insurer regarding any standard your locks should meet.
Most home insurance won’t offer cheaper insurance for BS3621 locks though as this is usually a standard requirement. Again we recommend checking with providers to see if having your locks to meet this standard will reduce your cost of insurance.
Kitemark on a BS3621 Approved Nightlatch
The estimated prices of British Standard BS3621 locks are as follows:
For estimated prices of changing and fitting locks see our locksmith price list here our guide even includes a pricelist checklist.
There are two other standards you will see mentioned alongside BS3621 and that is BS8621 and BS10621, these are rarely used in domestic homes.
Used in Flats & Apartments – You will find BS8621 and BS10621 used in commercial properties & building with multiple occupants such as flats and apartments, although BS10621 is the least common.
BS8621 is a standard of lock which is used for emergency exits in the event of an emergency (IE fire), so you do not need a key to escape the building.
The benefit of having a BS8621 lock is if as follows:
Note: This standard of lock is not to be confused with a fire escape/panic bar.
There are two steps you can take to check your lock is a BS8621 lock:
Below are all the available versions of BS 8621 Kitemarked locks:
BS10621 is a mixture of keyed and keyless egress (dual mode ) and one of the least popular British standard of lock.
Warning: BS10621 locks should not be used in single exit dwellings because of the entrapment possibilities
The two simple steps to check your lock is a BS10621 lock are:
Below are all the available versions of BS 10621 Kitemarked locks:
To check your current locks are approved to BS3621 you should look for:
Also, don’t forget a Mortice lock must have at LEAST 5 levers to conform to BS3621.
If you are looking to upgrade your existing door locks to BS-3621, you should contact a local locksmith who will be to advise.
Prices – See our estimated prices of BS3621 approved locks our price guide even has a checklist of questions to ask the locksmith.
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