Lock changes between tenancies, lost keys, tenant lockouts and security upgrades for letting agents, landlords and property managers. Available 24 hours a day from our base in Knightsbridge, SW7.
Every time a rental property changes hands, the question is the same: who still has a key? Previous tenants, their family members, cleaners and contractors may all have held copies. A professional locksmith who changes the locks quickly between tenancies is one of the simplest ways to keep a rental property secure.
Knightsbridge Locksmith works with letting agents and landlords across Knightsbridge, Belgravia, Chelsea, Kensington and central London. We change locks between tenancies and deal with lost keys and tenant lockouts. We fit insurance-approved locks, and agencies with an account with us are invoiced by property address.
This page also answers the questions agents and landlords ask us most. When can you change the locks? What notice do you need to give? What happens if tenants change the locks themselves?
A lock change between tenancies means the new tenants are the only people with keys to their home. On most doors we don’t need to replace the whole lock. We fit a new cylinder, or rekey the existing lock, and hand over a fresh set of new keys.
| Lock type | Typical rental property | Lock change option |
|---|---|---|
| Euro cylinder | Modern flats, uPVC and composite doors | New anti-snap cylinder, same day |
| Rim cylinder night latch | Period flats and mansion block front doors | New cylinder, or a BS3621 night latch |
| Five-lever mortice deadlock | Timber front doors and townhouses | Rekey, or a new BS3621 lock |
| Banham locks | Many SW1, SW3 and SW7 flats | Banham lock change (new registered keys) |
| EVVA and Assa Abloy cylinders | Mansion blocks and managed buildings | EVVA lock change or Assa Abloy cylinder to match the building |
We change the locks once the previous tenants have moved out and returned their keys, ideally before the check-in inventory. The new tenants then receive keys that have never left your control.
Landlords change the locks on a rental property for three main reasons. It protects the new tenants, it protects the property, and it helps protect the landlord if something goes wrong.
For agents managing many properties, changing the locks between tenancies is one of the cheapest security measures available.
When a tenant loses keys, the first question is whether the keys can be linked to the address. A bag or wallet stolen with ID inside, or a key fob with the flat number on it, is a real security risk. In that case, change the locks the same day.
We can usually change the locks within the hour in Knightsbridge, and give the tenant new keys on the spot. You also get a receipt with the details of the new lock for your records.
During a tenancy, generally no. The tenant has exclusive possession of the rental property, and the right to “quiet enjoyment” of their home. A landlord or letting agent who changes the locks to keep a tenant out, without a court order, is likely to be committing an illegal eviction under the Protection from Eviction Act 1977. That is a criminal offence, and it applies even when the tenant owes rent.
Since the Renters’ Rights Act came into force on 1 May 2026, Section 21 “no-fault” notices have been abolished. Landlords in England who want possession must use Section 8 eviction proceedings, prove a legal ground, and get a court order. Only then can bailiffs enforce the order. Changing the locks is never a shortcut around that process.
There are certain conditions under which a landlord can lawfully change the locks:
In every case during a tenancy, the tenant must get a key straight away. A landlord can change the locks, but should not keep the only set of keys to the tenant’s home.
As a professional locksmith, we won’t change the locks to lock out a tenant who is still living in the property. If you’re not sure where you stand, please seek advice from a solicitor or your letting agent before booking.
A landlord owns the rental property, but the tenant’s home is theirs to live in without interference. So before entering, or arranging any work inside, landlords and agents need to give proper notice.
In a genuine emergency, where there’s an immediate risk to people or the property, a landlord or agent may be able to gain access without the usual notice. Examples include:
After an emergency entry, tell the tenant straight away what happened and why. If a lock was damaged getting in, we’ll replace it and give the tenant new keys. Emergency door opening
It depends on the tenancy agreement. Most agreements say tenants must not change the locks without the landlord’s permission. If yours does, a tenant who changes the locks anyway is in breach of the tenancy.
If the agreement doesn’t mention locks, tenants may be able to change them, because it is their home. Even then, these conditions usually apply:
For letting agents, if a tenant changes the locks without permission, bring it to the tenant’s attention in writing and ask for a key. Keep a record of the correspondence.
When a rental property has been broken into, the tenant needs to feel safe again the same night. Call the police first for a crime reference, then call us on 07309 909989.
Other security risks that call for an urgent lock change include a tenant losing keys, a relationship breakdown where one person has moved out, and keys held by a former cleaner or contractor.
Locks wear out like everything else in a rental property. Adding them to your property maintenance plan prevents lockouts, insurance problems and emergency call-outs.
We don’t currently fit smart locks. Many landlords still choose high-security mechanical locks, because they meet the standards insurers usually ask for. Read more in our guide to home security trends in London.
Regular maintenance helps protect the tenants, the property and the landlord, and costs far less than dealing with a break-in.
| Service | What we do |
|---|---|
| Lock change between tenancies | New cylinders or rekeying after the previous tenants move out, with new keys for the new tenants |
| Lost keys | Urgent lock change and new keys, often within the hour in Knightsbridge |
| Tenant lockouts | Non-destructive entry wherever possible, after we verify the tenant’s ID. Locked out of a flat or a house |
| Snapped or stuck keys | Broken keys removed without damaging the lock. Snapped key in a Banham lock |
| Break-in repairs | The property made secure the same night, with new keys for the tenant |
| Void property security | Locks changed and doors secured while a rental property is empty |
| Communal doors | Entrance doors, door closers and communal locks in mansion blocks |
| Banham locks | Changes, repairs and openings, common in SW1, SW3 and SW7 |
| Master keying | One key for the managing agent, while each tenant’s key opens only their own flat |
The cost depends on the lock type, the security grade and the time of day. Changing a cylinder costs much less than replacing a whole lock, and Banham locks cost more because the keys are registered. See our prices, or call for a quote.
We’re based at 4 Montpelier Street, SW7, and work with letting agents and landlords across Knightsbridge, Belgravia, Chelsea, Kensington, South Kensington, Brompton, Brompton Square, Cadogan Square, Hans Town, Sloane Square, Hyde Park and Westminster. Most addresses in Knightsbridge are reached in 10–15 minutes, and the surrounding areas in 15–20 minutes. We cover other parts of central London too. Call to check, or see our full service area.
Managing commercial property as well? See our commercial locksmith services.
There’s no legal requirement in England to change the locks between tenants, but it’s strongly recommended. You can’t be sure previous tenants returned every copy of the key, and some landlord insurance policies won’t pay out if a burglar used an old key.
Not during a tenancy. Changing the locks without the tenant’s permission can breach their right to quiet enjoyment. If it keeps them out of their home, it can amount to illegal eviction. Between tenancies, once the previous tenants have left, landlords can change the locks freely.
No. Rent arrears don’t give a landlord the right to lock a tenant out. The landlord must use Section 8 eviction proceedings and get a court order. Since 1 May 2026, Section 21 notices are no longer available in England.
If the tenancy agreement forbids it, no, and doing so is a breach of the tenancy. If the agreement is silent, tenants may be able to, but they should keep the original lock fittings, avoid damaging the door, and give the landlord a key.
At least 24 hours’ written notice for inspections and repairs, at a reasonable time. In a genuine emergency, such as a gas leak or fire, access may be needed without notice.
Usually the tenant, depending on the tenancy agreement. That can include a lock change if the lost keys create a security risk. Unpaid costs may be claimed from the tenant’s deposit at the end of the tenancy.
Yes, most agents and landlords keep a key for emergencies and for access with proper notice. Holding a key doesn’t give the right to enter without notice, except in an emergency.
We only open a door for someone who can prove they live there, or when the landlord or agent confirms who they are. This prevents unauthorised access to a tenant’s home.
Payment is due on the day of the job, by card, cash, Apple Pay or Google Pay. Agencies with an account or contract with us are invoiced instead, itemised by property address. Call us to set up an account.
Yes. We work 24 hours a day, 365 days a year. See our emergency locksmith services.
Call the local team for a lock change between tenancies, lost keys or an emergency. We’ll be with you in minutes across Knightsbridge.
Knightsbridge Locksmith, 4 Montpelier Street, Unit 162, London SW7 1EE. Open 24 hours, 7 days a week.
This page gives general information about the law in England as of 2026. It isn’t legal advice. Rules differ for UK landlords in Scotland, Wales and Northern Ireland, and your own tenancy agreement matters. If you’re unsure of your rights or legal obligations, seek advice from a solicitor, your letting agent or Shelter before acting.
