Should I Change the Locks If I’ve Lost My Keys?

Only if your keys could lead somebody to your door. If anything with your address on it went with them, or they were stolen rather than dropped, change the locks before you spend another night in the house. If they genuinely cannot be traced back to you, you need a way in and a spare cut, not new locks.

That is the short answer. Here are two jobs that started with exactly the same sentence on the phone, “I have lost my keys”, and ended completely differently.

Ten o’clock at night, suitcases on the doorstep

A family in Canons rang me at ten o’clock one night. They had just got back from a holiday abroad, a hotel in the middle of nowhere, and they were standing on their own doorstep with the suitcases, a flight and a drive from the airport behind them, and no keys. The keys were still in the hotel room.

The first thing they asked was whether they needed new locks.

So I asked where the keys were. Not “lost” where. Actually where. In a hotel room a few hours’ flight away, about to be found by a cleaner and handed in at reception. Nobody there had any reason to come to Harrow, and nobody who might want to had the faintest idea the keys existed.

Lost, and “we know exactly where they are”, are not the same thing.

I opened the door without damage, they carried the suitcases in, and the keys came back in the post a few days later. No new locks. Their keys simply had a longer holiday than they did.

Now picture the same doorstep with a different locksmith on it. A tired family, two children, ten o’clock at night, and a man who says “to be safe, we should change them”. They would have agreed to anything, paid for new locks they did not need, and thanked him on the way in. He would not have had to lie to do it. He would just have had to not ask where the keys were.

The bag on the Metropolitan line

The second job went the other way.

A woman from Northwick Park had her bag stolen on the tube on the way home. Her house keys were in it, and so were her documents, driving licence included. A UK driving licence has your address printed on the front.

So whoever had that bag did not have a key to some door somewhere. They had a key, and the address of the door it opens. Not might have. Had.

She was locked out as well, so I opened the door first. Then I changed the locks before I left. She did not spend a single night in that house behind a lock that somebody else had a key to.

Both customers lost their keys. Only one of them lost them to somebody who knew where she lived. That difference is the whole post.

The one question that decides it

Can your keys lead somebody to your door? Go through this honestly:

• Was anything with your address on it with them? A driving licence, a letter, a parcel card, or a tag on the keyring with your house number on it. (If your keyring has your address on it, take it off today, whether you have lost your keys or not.)
• Were your car keys on the same ring? If they were lost anywhere near home, a car key is a very good way of finding a car, and your car is parked outside your front door.
• Did you lose them near home? Your own street, your local station, the shop on the corner. The closer to the door, the shorter the walk back to it.
• Were they taken, or dropped? Somebody who steals a bag goes through it on purpose. Somebody who finds keys on a bench usually hands them in or leaves them on a wall.
• Is there a building fob or a flat number on the ring? On a block of flats, the fob gets them through the front door of the building, and the number tells them which door is next.

If the answer to any of those is yes, change the locks today. If every answer is no, the keys went missing a long way from home with nothing attached and nobody saw them go, the risk is very low. A key on its own, with nothing to say whose it is, opens one door in the whole of London, and whoever is holding it has no idea which one.

And if you honestly do not know? If they vanished somewhere between the station, the pub and your sofa and you cannot rule anything out, treat it as a yes. A new cylinder is a small job. Lying awake listening for the front door is not.

Tonight, or tomorrow morning?

This is where a lot of people end up paying for urgency they do not have. There are really only three situations.

Stolen, or lost with your address: tonight. Before you sleep there. If you are locked out as well, the lock change happens on the same visit as getting you in, which is exactly what happened in Northwick Park.

Lost with nothing attached, and you have a spare: no rush. You do not need a locksmith tonight. Get another spare cut so you are not down to one, and if you want the peace of mind of new locks, book it in the daytime when it suits you. My key cutting page covers the spare.

Lost with nothing attached, and you are locked out: get in tonight, decide about the locks in daylight. That is the Canons family. A locked door is tonight’s problem. A lock change is a decision, and decisions made on a doorstep at ten o’clock at night are rarely the good ones.

What “changing the locks” actually means

On most modern doors a lock change is a much smaller job than people imagine, and it only covers the locks those keys actually fit.

uPVC and composite doors have a euro cylinder, the part the key goes into. Changing it is one screw and a new cylinder. The multipoint mechanism in the door stays exactly where it is. Since you are changing it anyway, have a 3-star anti-snap cylinder fitted on the front door rather than a basic one. If you do not know why that matters, read what lock snapping is first.

Timber doors usually have a mortice lock, and that is the lock that gets changed. On a front or back door it should be a British Standard lock, and if you are not sure what that looks like, my post on what a BS3621 lock is shows you where to find the stamp.

Only change what the keys fit. If the lost ring had the front door key and not the back, the back door is fine. If the garage key was on it, the garage needs doing too, and I cover those under garage, gate and shed locks.

Locked out as well?

If you are reading this on your phone outside your own front door, my post on what to do when you are locked out covers the next half hour.

One thing to listen for when the locksmith arrives. A good one asks where your keys are before he says a word about new locks. If he goes straight to “we will need to replace these”, and you know your keys are sitting in a hotel in another country, you are entitled to say no.

The spare keys you still have

The moment the locks are changed, every old key becomes a key to nothing. That includes the spare in the kitchen drawer, the one the neighbour keeps, the cleaner’s and the one your mum has had since you moved in.

So before the locksmith leaves, count who needs a new one and get enough cut. And while you are counting, it is worth asking how many of those old keys you could actually have accounted for. If the answer surprises you, I wrote about exactly that in my post on changing the locks when you move into a new house.

If your spare lives under a flowerpot, that is a separate conversation.

Will your insurance help?

It might. Many home insurance policies include some cover for replacing the locks when keys are lost or stolen, sometimes as part of contents cover and sometimes as an extra. There is usually an excess and a limit. Read your own policy rather than trusting a blog, mine included.

If the keys were stolen, report it to the police. Your insurer will usually want a crime reference number before they will talk about a claim.

And there is a second reason not to wait. If somebody lets themselves in with your stolen key, there is no broken glass, no damaged frame and no forced entry. The first thing an insurer will want to understand is how they got in, and that is a harder claim than one with a splintered doorframe attached to it.

And if you rent

Tell your landlord or your agent straight away, in writing, and say exactly what happened, including whether anything with the address on it went with the keys.

Do not change the locks yourself without their agreement. The locks are not yours to change, and doing it anyway can put you in breach of your tenancy. If the keys were stolen with your address, most landlords will agree to a change the same day. Who pays depends on your tenancy agreement, so read it.

If you are the landlord and a tenant rings you with this, treat a stolen bag with an address in it as urgent. It is your property too.

What I would actually do in your position

Work out where your keys actually are. Not “lost”. Where. A hotel, a friend’s car, the bottom of the river, a stranger’s pocket.

Then check what was with them. Address, car keys, building fob. That one check decides everything else.

If they can lead somebody to your door, change the locks the keys fit before you sleep there. If they were stolen, get a crime reference number and ring your insurer.

If they cannot, do not let anybody sell you new locks at ten o’clock at night. Get in, get a spare cut, and decide in daylight.

A lock seller hears “I have lost my keys” and starts thinking about which locks to sell you. I start by asking where they are. Sometimes the answer is new locks before bedtime. Sometimes it is a hotel in the middle of nowhere and a padded envelope in the post. Either way, you only pay for the one you need.

Common questions about lost keys and changing locks

Should I change my locks if I’ve lost my keys?

Only if the keys could lead somebody to your door. If anything with your address on it was with them, such as a driving licence, a letter or an address tag, or they were lost near your home, or they were stolen rather than dropped, change the locks before you spend another night in the house. If they were lost a long way from home with nothing attached, the risk is very low and you usually need a spare key cut rather than new locks. If you honestly cannot say where they went, treat it as a yes.

Do I need to change the locks if my keys were stolen?

Yes, if anything with your address on it was stolen with them, and that includes a driving licence, which has your address printed on it. Whoever has your bag then has a key and the address of the door it opens. Change the locks the keys fit the same day, before you sleep in the house, and report the theft to the police so you have a crime reference number for your insurer.

How soon should I change the locks after losing my keys?

It depends on whether the keys can be traced to you. If they were stolen, or lost with your address, change the locks the same day, before nightfall if you can. If they were lost with nothing attached and you have a spare, there is no rush and a daytime appointment is fine. If you are locked out and the keys cannot be traced to you, get back in tonight and decide about the locks in daylight.

What if my car keys were on the same keyring as my house keys?

Treat it as more serious. If the keys were lost anywhere near home, a car key is an easy way to find a car, and the car is usually parked outside the house. That links your house keys to your address, so change the locks they fit the same day. If they were lost a long way from home, for example abroad or at the other end of the country, the risk is much lower.

Do I need to change the whole lock or just the cylinder?

On a uPVC or composite door, usually just the cylinder. It is the part the key goes into, and changing it means the old keys stop working while the multipoint mechanism in the door stays in place. On a timber door with a mortice lock, the mortice lock itself is changed. Only the locks the lost keys fit need doing.

Does home insurance cover changing the locks if I lose my keys?

Many home insurance policies include some cover for replacing locks when keys are lost or stolen, sometimes within contents cover and sometimes as an optional extra, usually with an excess and a limit. Check your own policy wording. If the keys were stolen, report it to the police first, because insurers usually ask for a crime reference number.

I rent. Can I change the locks if I’ve lost my keys?

Not without your landlord’s or agent’s agreement. Tell them straight away, in writing, and say whether anything with the address on it went with the keys. Changing the locks without permission can put you in breach of your tenancy. Most landlords will agree quickly if the keys were stolen with the address. Who pays depends on your tenancy agreement.

Lost your keys and not sure which one you are?

Ring me, tell me where the keys went and what was with them, and I will tell you straight whether you need new locks tonight or just a way in.

Call Andrew: 073 7617 6366 Or contact me at: andrewthelocksmith.com/contact-andrew-the-locksmith