How often should you change your locks? Signs it's time

If you have ever stood on your doorstep wondering whether the lock on your front door is past its best, you are not alone. The question of how often you should change your locks comes up with almost every homeowner, tenant and landlord we speak to in Manchester, and the honest answer is that there is no fixed interval. A lock is not like a boiler service or an MOT.

What matters is the condition of the lock, the standard it was built to, and what has happened to your keys. This guide sets out the events that should always trigger a change, the wear signs that are easy to miss, and how to tell when a repair will do and when replacement makes more sense.

There is no set schedule, only triggers

Good locks are mechanical and simple. A decent cylinder or mortice lock, fitted properly and used normally, can last well over a decade. Cheap ones may not. So instead of a calendar date, think in terms of triggers: events that make a change sensible regardless of how old the lock is.

The most important triggers are about who has keys, not about metal fatigue. A brand-new lock is no use if a former partner, tenant or tradesperson still holds a working key. For that reason the list below matters more than any age.

The events that should always prompt a change

Change or rekey the locks promptly if any of the following happens:

You lose a set of keys, or they are stolen, particularly if an address went with them.
You move into a new home. You cannot know how many copies the previous owners or tenants made. We cover this in detail in our guide to changing locks in a new house.
A relationship ends and someone who lived with you still has a key.
A tenant moves out, or a lodger, cleaner or contractor who held a key stops working for you.
There has been a burglary or attempted break-in, even if the lock appears to have held.

In most of these cases, rekeying is enough. Rekeying alters the internal pins so the old keys no longer turn, and it costs far less than a new lock. Our article on whether to rekey or change the lock after losing keys explains how to choose between the two.

Wear signs that are easy to ignore

Locks rarely fail without warning. They usually complain for months first, and the complaints are easy to put up with. Watch for these.

The key is stiff, gritty or needs jiggling

A key that has to be wiggled, pushed in hard or turned with force is telling you something. Sometimes it is dirt or a cold snap, which we look at in why a door lock goes stiff. If cleaning the lock and adding a little suitable lubricant does not cure it, the pins or springs inside may be worn. A stiff lock that finally refuses to turn is the classic cause of an emergency call at the worst possible time.

The key is worn, or the lock only works at one angle

Keys wear too. If your copy is smooth and shiny, or a copy made from a copy, it can wear the lock internals unevenly. A lock that only turns if the key is held at a particular angle is already part way through failing.

The handle is loose or the door needs lifting

On a uPVC or composite door, the cylinder is only one part. The multipoint mechanism, the strip of locking points running up the edge of the door, does most of the work. If the handle feels loose, drops when released, or you have to lift it hard to lock, the gearbox or the door alignment may be at fault. Left alone, this puts strain on the cylinder and the keep plates. Our uPVC door repair service deals with exactly this, and a repair is often all that is needed.

The cylinder sticks out or looks cheap

A euro cylinder that protrudes noticeably from the door furniture is a weakness, because it gives a burglar something to grip and snap. Many builders fitted basic, unrated cylinders to doors across Manchester over the years. If yours is in that camp, age is irrelevant: it is a reason to upgrade. We explain the difference in our guide to whether anti-snap locks are worth the extra cost.

Visible damage, rust or play in the door

Look at the lock, the keep and the door edge. Splintered wood around a mortice, rust, bent keeps, a lock body that rattles in its recess, or marks that suggest someone has tried to force it all deserve attention. A door that has been kicked once may have a weakened frame even if it still opens normally.

Quality matters more than age

Two locks of the same age can be in very different shape because they were built to different standards. This is the part many people miss.

On a wooden front door, the benchmark is a five-lever mortice deadlock to British Standard BS3621, which is also what many home insurers ask for on final exit doors. If you are not sure what that means for your policy, we explain it in BS3621 explained. A BS3621 lock in good condition is worth keeping, even if it is decades old.

On a uPVC or composite door, look for a cylinder that carries the TS 007 3-star or Sold Secure Diamond marking, which is designed to resist snapping, drilling and picking. A plain cylinder with no marking is a candidate for replacement now, whatever its age.

Check your home insurance documents too. Some policies set specific lock requirements, and a lock that does not meet them can cause trouble when you come to claim. Reading the small print costs nothing and can save a great deal.

Repair, rekey or replace?

It helps to have a rough rule of thumb.

Repair or adjust when the problem is mechanical but the lock is of decent quality: a loose handle, a door that has dropped, a worn keep or a mechanism that needs servicing.

Rekey when the lock itself is sound and the only issue is who has keys.

Replace when the lock is below standard, worn out, damaged, or no longer matches your insurer's requirements. As a guide, a replacement cylinder generally runs from about £80 to £180 fitted, and a 3-star anti-snap model from about £140 to £250. A BS3621 mortice fitted is typically £140 to £280. Prices vary with the door, the lock model and the time of day, so treat these as ranges and ask for a firm quote.

Our lock replacement page explains the options in more detail.

What it looks like around Manchester

The right answer depends on the house. The Victorian and Edwardian terraces in Didsbury often have original timber doors, where the question is usually the condition of an old mortice and whether it meets BS3621. Check the keep, the door edge and the age of the key.

In Withington, where there is a high turnover of student and shared houses, the main trigger is keys changing hands. Many tenants leave with a set and the next group arrives to a lock that has not been touched for years. A quick rekey at the start of each tenancy is cheap and sensible.

Across the newer housing estates, uPVC and composite doors dominate, so the cylinder standard and the health of the multipoint mechanism are the things to look at.

A simple yearly check

You do not need to be a locksmith to keep an eye on your locks. Once a year, take ten minutes to do the following on each external door:

Turn the key and listen. It should feel smooth, with no grating.
Close and lock the door with the handle lifted and see whether it needs force.
Check the cylinder sits flush and carries a security marking.
Look at the keep plates and frame for cracks or looseness.
Count the keys. If you cannot account for every set, think about rekeying.

When to call a locksmith

Call a locksmith when a lock is stiff, loose or failing, when keys have gone missing, when you move in or a tenant leaves, or when you are unsure whether your locks meet your insurer's requirements. Do not wait until the lock jams shut, because a planned visit is nearly always cheaper and calmer than an emergency one. We can assess the lock, tell you plainly whether it needs a repair, a rekey or a replacement, and avoid selling you more than you need.

Final thoughts

So, how often should you change your locks? When a trigger appears, not on a timetable. Lost keys, a new home, a changing household, signs of wear, or a lock that no longer meets the standard your insurer expects are all good reasons. Otherwise a sound, rated lock that works smoothly can stay for years.

If you are unsure about the locks on your own doors, get in touch with Manchester Locksmith 24 for an honest assessment and a clear quote before any work starts.