Updated
Key Snapped Off In The Lock
The key has broken, leaving part of it inside the barrel, and the rest is in your hand.
Find a locksmith
What's happening?
A key almost never snaps without warning. It fails because it has been under sustained twisting force for weeks or months — and the reason it is under that force is nearly always that something else is out of line. The door has dropped, so the bolt is scraping into the keep rather than sliding in. The cylinder is dry and full of grit. Or the key itself is a worn copy of a copy, cut slightly shallow, so it no longer lifts the pins cleanly and needs jiggling and pressure to work. Brass keys are soft by design, so the key is the part that gives. Once it has snapped, the working half is still sitting inside the plug, holding the pins in position. Getting it out without damaging the cylinder is a specific extraction job, and pushing anything into the keyway usually drives the broken piece further in.
What usually causes it?
- The door or the frame dropped, so the bolt binds in the keep and the key takes the strain
- A worn key, or a copy cut from another copy, that no longer matches the pins properly
- A dry, gritty or corroded cylinder needing more force every time it is turned
- Cold weather thickening old oil-based lubricant inside the mechanism
- A bent key that has been straightened and refitted, leaving a weak point
- Using the key as a lever to push or pull a door that is binding on the frame
- A failing lock mechanism that has been stiffening for weeks and was never looked at
Is it dangerous?
Not physically, but it usually leaves you either locked out or unable to lock up, and a house that cannot be secured overnight is a genuine problem rather than an inconvenience. A broken key jammed in a final exit door is worse again, because it can stop the door being opened quickly from inside.
Can I fix it myself?
Very little, and the wrong attempt makes it much more expensive. Do not push the other half of the key back in to try to turn it, and do not poke a screwdriver, a paperclip or superglue into the keyway — glue in a cylinder means a new cylinder every time. If the broken end is visibly proud of the face and the lock is in the unlocked position, gripping it square-on with fine pliers and pulling straight out sometimes works. If it does not come first time, stop.
When should you call a locksmith?
Call a locksmith straight away, especially if the broken piece is flush or below the face of the cylinder, if the lock is in the locked position, or if the door is a final exit. Say on the phone that a key has snapped in the lock — extraction needs specific tools, and it is a different job from an ordinary lockout. Ask for a total price before anyone travels.
What will the locksmith actually do?
- Extract the broken section with key extractor tools, without damaging the plug or the pins
- Test the cylinder and the mechanism to find out why the key was under enough load to break
- Check the door alignment, the keep and the bolt travel, since binding is the usual root cause
- Clean and lubricate the cylinder correctly, or replace it where it is worn or corroded
- Cut fresh keys from the code or the lock rather than copying a worn key, and check every key turns freely
Frequently asked questions
We’re happy to answer all your questions.
Need a locksmith?
Compare local locksmiths on Tradehand — coverage areas, accreditations and phone numbers, no middleman.