Lost Or Snapped Keys? Here's What Actually Happens Next.

A key that snaps in the lock almost never does it without warning. It bends slightly for weeks, needs a particular angle, gets stiff in cold weather, and then shears off on an ordinary morning. Once part of the blade is inside, the mechanism is jammed part-way through its travel and the door is neither properly locked nor openable.

The most important advice is what not to do. Pliers push the fragment deeper and score the pin chamber. Superglue on a matchstick bonds the fragment to the cylinder and turns a ten-minute extraction into a guaranteed replacement. Drilling it yourself destroys a lock that was very likely salvageable. Every one of these is understandable at the time, and every one of them adds cost.

Proper extraction uses purpose-made tools that hook the fragment and draw it out along the keyway, and in most cases the cylinder survives completely intact. Where the break is deep, or where a previous attempt has jammed it further, extraction takes longer but is still usually possible. It genuinely is worth calling before trying anything, because the difference in cost between the two outcomes is substantial.

The part that matters afterwards is why it happened. Keys shear because they have been fighting something — a worn cylinder whose pins no longer line up cleanly, or a door that has dropped so the bolt catches its keep and needs force to turn. We check both before leaving. If the cylinder is worn out, we will tell you and quote a replacement; if the door needs adjusting, we will adjust it. Extracting the key and leaving the cause in place simply schedules your next snapped key.

• Snapped key extraction from euro cylinders
• Mortice and nightlatch key extraction
• Cylinder usually saved, not replaced
• Cause diagnosed — wear or door alignment
• Anti-snap replacement if the lock has failed
• Attended 24 hours a day

A broken key that came apart in your hand rather than in the lock is a slightly different problem, and often a more useful one, because you still have both halves and the lock is not jammed. It is also a clear warning: that key was at the end of its life, and any copies cut from it recently will be carrying the same weakness.

Keys wear invisibly. Every use abrades the cuts slightly, and after years the profile no longer matches the pin heights it was made for. The lock compensates for a while, then starts needing a jiggle, then needs a particular lift or angle. That is the point at which people start describing the lock as having a knack — and a key doing extra mechanical work to overcome a poor match is a key building toward a break.

The common mistake is cutting a new key from the worn one. A copy taken from a degraded key reproduces the degradation and sometimes amplifies it, which is why a fresh copy can work worse than the original. Where an original or a code exists, cutting from that gives a correct key. Where it does not, and the cylinder is worn to match, replacing the cylinder and starting again is often the more sensible answer.

Bent keys deserve a mention because straightening them is such a natural instinct. A key that has been bent and straightened has been work-hardened at the bend, and that point is now brittle and considerably more likely to shear — usually inside the lock, where it becomes a much larger problem. A bent key should be replaced rather than corrected.

• Broken key replacement cut correctly
• Worn key and cylinder assessment
• Keys cut from original or code, not a worn copy
• Bent key advice — replace rather than straighten
• Cylinder replacement where wear is matched
• Spare sets cut while on site

Losing keys raises one question that actually matters: can whoever finds them work out where they fit? That single answer determines everything else, and it is worth thinking through calmly rather than deciding in the first ten minutes.

If your keys were on a ring with an address fob, a parcel label, a work pass, or anything identifying, treat the property as compromised and change the locks. The same applies if they went missing close to home, or if they disappeared with a wallet or bag containing your address. In those cases the lock change is not paranoia, it is proportionate, and it should happen the same day rather than at the weekend.

If they vanished on holiday two hundred miles away with nothing identifying attached, the realistic risk is very low. Most lost keys are genuinely lost rather than taken, and the finder has no way of matching them to a door. We will say this plainly rather than talking you into work you do not need — we would rather cut you a replacement set and be called again next year than sell an unnecessary lock change today.

Where a change is warranted, it is usually only the cylinder that needs replacing on a uPVC or composite door, which keeps cost and disruption low. Every external door should be done together, including the back door and any side gate, and it is worth keying them alike so the household carries one key rather than four. On timber doors the mortice lock body is changed, and we fit to BS3621 so your insurance position is not quietly weakened in the process.

• Same-day lock change after key loss
• Honest assessment of actual risk
• Cylinder-only change where appropriate
• All external doors done together
• Keyed-alike sets to reduce key count
• BS3621 hardware on timber doors

Keys locked inside is the most common key call we take and the least serious, because nothing is actually broken. Your keys are safe, your lock is fine, and the only problem is which side of the door you are standing on. It is also the situation where panic costs the most money, because the lock is in perfect working order right up until somebody forces the door.

On a nightlatch this happens simply by pulling the door shut. On a uPVC door it usually means the door was locked with the key from outside and the keys were then put down inside, or a second person left later. Either way, the fix is entry rather than repair, and in the vast majority of cases entry is achieved without damage using picking or bypass techniques appropriate to the lock.

The instinct to try a window first is worth resisting. Ground-floor windows in London are frequently restricted, and a window forced open or a pane broken costs several times an entry callout and leaves the property less secure until it is repaired. Climbing in through anything above ground level is a genuinely bad idea, and we would much rather attend than have somebody attempt it.

You will be asked to demonstrate you are entitled to be there. That is not obstruction, it is basic practice, and it exists to protect you as much as anyone — a locksmith who lets anybody into any property on request is not one you want operating in your area. Post, ID showing the address, or a phone call with someone who can confirm it is normally sufficient, and our engineers are used to handling it quickly and without making it awkward.

• Non-destructive entry as the default
• Nightlatch and uPVC door lockouts
• No repair needed — nothing is broken
• Attended 24 hours a day
• Straightforward proof-of-entitlement process
• Spare keys cut while on site

A lost key at work is a different calculation from a lost key at home, because you are deciding on behalf of other people. A missing office key, a communal entrance key, or a stockroom key affects everyone in the building, and the person who lost it is rarely the person who bears the consequence.

The awkward part is that nobody knows how many copies exist. On a standard key profile, any keyholder can have a copy cut at a kiosk for a few pounds without telling anybody. Over years of staff turnover in an office, or decades of tenancy changes in a block, the number of keys in circulation drifts well beyond any list anybody is keeping. When one goes missing, you are not losing one key from a known set — you are losing one from an unknown one.

This is exactly the problem restricted key profiles solve. Blanks are controlled and cut only against your written authorisation, so every key in existence is one you approved. It costs slightly more per key and it converts a lost key from a lock-change decision into an administrative note. For communal entrances in blocks of flats, it is generally the single most useful security change a managing agent can make.

Where a key is lost on a standard profile and the risk is real, changing the cylinder on the affected door is the honest answer. For suited or master-keyed systems this is more involved, because the new cylinder has to be cut into the existing hierarchy correctly, and we would rather do that properly than compromise the whole system for one door.

• Office and communal key loss handled
• Restricted profiles to control copying
• Cylinder changes within suited systems
• Managing agent and landlord accounts
• Key schedules kept on record
• Written record of what was changed

Almost every call on this page could have been avoided by a spare key existing somewhere sensible. It is the least interesting advice in locksmithing and by some distance the most effective, and the reason people do not act on it is simply that the moment it matters is the moment it is too late to arrange.

Somewhere sensible means with a person, not in a place. Every outdoor hiding spot is a known one — under the mat, in the meter box, beneath the third plant pot, inside the fake stone that looks like every other fake stone sold in Britain. Anyone who does this professionally checks all of them in under a minute. A neighbour you trust, a family member nearby, or a keysafe fitted where it is not visible from the street are all genuinely better.

If you use a keysafe, the details matter. It should be police-approved to LPS 1175 rather than the cheapest unit available, positioned out of sight of the street, and its code should be changed whenever anyone who knew it no longer needs access. A visible keysafe on a front wall with a code that has not changed since it was fitted is an advertisement rather than a precaution.

The other habit worth building is acting on early warnings. A key that has started needing a wiggle, a lock that is stiff in the cold, a door that needs lifting — these are all mechanical faults announcing themselves in advance. Addressed as planned work they are inexpensive. Addressed at the point of failure they are an out-of-hours callout, usually in the rain.

• Spare sets cut while we are on site
• Police-approved keysafe supply and fitting
• Advice on where spares should actually live
• Restricted keys so copies stay controlled
• Early-warning faults diagnosed cheaply
• Cylinder condition checked on any visit