Key Won't Turn in the Lock: What to Do

Lock problems rarely appear without a reason, and most cases fall into a handful of well-understood categories. The most common on London front doors is a worn or damaged cylinder. Over years of daily use, the internal pins inside a euro cylinder or a Yale barrel gradually wear down. The key still enters cleanly, but the tolerances have shifted just enough that it can no longer push those pins to the precise height needed to allow the barrel to rotate. You will often notice this creeping in gradually — the key starts requiring a bit of extra effort before one day it simply stops working altogether.

A second very common cause is a dropped or sagging door. Timber doors expand and contract with the seasons, and the older Victorian and Edwardian terraces that make up so much of Kentish Town's housing stock are particularly prone to this. When a door drops even a few millimetres on its hinges, the latch or bolt is no longer aligned with the keep in the frame, and the lock cylinder has to work against that pressure. The key turns fine in isolation, but under load from the misaligned door it cannot rotate. Debris is a third culprit — dust, grit, old lubricant that has hardened, or even a small fragment of a previously broken key lodged inside the barrel can all jam the mechanism. On uPVC and composite doors, problems with the multipoint locking mechanism itself — the long strip of hooks and bolts that runs up and down the door edge — can create the same stiff, immovable feeling at the handle or cylinder even when the cylinder itself is undamaged.

Before anything else, check the obvious: are you using the right key? It sounds unnecessary, but on a key ring with several similar-looking keys it is a genuinely frequent cause of a 'stuck' lock. If you are confident it is the correct key, try applying very light inward pressure on the door while simultaneously attempting to turn the key — this can relieve the pressure on the bolt if the door has dropped slightly and is what prevents the cylinder from rotating freely. Do not force it. If it does not give with gentle pressure, stop.

For a lock that feels gritty or stiff rather than completely seized, a small amount of dry graphite lubricant or a PTFE-based spray applied to the key and worked gently into the keyhole can dissolve hardened debris and free the mechanism. Avoid WD-40 on locks — it is a water displacer rather than a true lubricant, and it attracts dust over time, making the problem worse. If none of these gentle approaches produces any movement within a minute or two, it is time to stop. Applying force — turning harder, using a tool for leverage, or striking the key — risks snapping the key inside the barrel, which turns a stiff lock into a completely blocked one and significantly increases the cost and complexity of the repair.

There are specific situations where you should put the key back in your pocket and call a professional straight away. If the key has already snapped or is visibly bent, further attempts will only push broken metal deeper into the barrel. If you can see that the cylinder is visibly damaged — particularly on a euro cylinder door, where cylinder snapping is a known and deliberate break-in technique — do not attempt to operate it at all; a damaged cylinder can sometimes be a sign of a tampering attempt. If the lock is on a uPVC door and the handle is also unresponsive, the multipoint mechanism has likely failed and the door needs specialist attention rather than DIY intervention.

If you are locked out of the house entirely and none of the above gentle steps have worked, the most sensible course of action is to check whether a window or back door is accessible and secured from the outside, or whether a trusted neighbour holds a spare key — these are the two legitimate self-help options worth trying before calling a locksmith. If neither is available, that is exactly what a 24 hour locksmith London service exists for. Our team at Kentish Town Locksmiths is available around the clock, every day of the year including bank holidays, and we send a locksmith straight away — we are usually with you in about 30 minutes. Call us on 020 7871 7825 and we will confirm an exact up-front price before anyone sets off.

Sometimes a stiff or non-turning key is a symptom of a lock that has simply reached the end of its useful life. Euro cylinders on uPVC and composite doors typically last between seven and fifteen years depending on usage and quality; mortice locks on timber doors can last longer but the internal springs and levers do eventually fatigue. If the cylinder is worn, loose in the door, or showing signs of corrosion, a lock change is often the more economical and reliable solution compared with repeated repairs.

A door lock replacement London homes benefit from most is an upgrade to a higher security standard at the same time — moving from a standard euro cylinder to an anti-snap, anti-pick TS007 3-star rated cylinder, for example, or ensuring a mortice lock meets BS3621, which most home insurers require on external doors. We carry a range of quality cylinders and mortice locks and can advise on the right specification for your door type, whether that is a solid timber door in one of Kentish Town's period conversions, a modern composite door on a newer development near Kentish Town Road, or the communal entrance door to a block of flats. If you are a tenant, we can also liaise with your letting agent or landlord where needed.

uPVC door lock repair London call-outs make up a large proportion of our work, and the reason is straightforward: multipoint locking mechanisms on uPVC doors are more complex than a simple cylinder and mortice, and they can fail in several distinct ways — a worn gearbox, a snapped rod, a fatigued keep, or a cylinder that has worked loose in its housing. The symptom is often a key that feels like it is turning but not fully engaging, or a handle that moves but does not throw the hooks. These faults require a trained eye to diagnose correctly; working on a failed multipoint mechanism without experience can leave the door in a state where it cannot be secured at all, which is a serious safety issue.

Prevention is straightforward and takes only a few minutes a year. Lubricate the cylinder and all moving parts of the lock with a dry graphite or PTFE product every six months. Check that the door is hanging level and that the keeps are aligned — if the door is visibly sticking or catching on the frame, have the hinges adjusted before the problem migrates to the lock. If you are in a period property, be aware that timber swells in damp weather; a lock that becomes difficult in winter and eases in summer is telling you the door needs attention, not just the lock. Attending to these small maintenance tasks early will almost always prevent the more disruptive and costly scenario of being completely locked out London on a wet evening with the key refusing to move at all. If you are unsure about the condition of any lock on your property, our experienced locksmiths are happy to carry out a security survey — just call 020 7871 7825, any time, day or night.