How to Fix a Door Lock That Is Stuck

A stuck door lock — whether the key won't turn or the bolt won't move — is stressful, especially when you're locked out or in. Here's how to diagnose and fix it safely.

Why Is My Door Lock Stuck?

• Dry or corroded lock cylinder: Lack of lubrication causes the pins to seize
• Misaligned door: The door has shifted so the bolt is under pressure against the strike plate
• Frozen lock: Moisture inside the cylinder has frozen in cold weather
• Worn key or cylinder: The key or lock pins are worn and no longer align properly
• Debris inside cylinder: Dirt, broken key fragments, or foreign objects blocking the pins
• Bolt jammed in extended position: The bolt mechanism is seized

Step 1: Don't Force It

Forcing a stuck lock can break the key inside the cylinder or damage the mechanism. Apply gentle pressure only while trying the fixes below.

Step 2: Lubricate the Lock Cylinder

This fixes the majority of stuck locks. Apply lubricant into the keyhole, insert the key, and gently work it back and forth.

• DuPont White Lithium Grease — excellent for lock cylinders, long-lasting
• WD-40 Multi-Use 3oz — good for penetrating rust and freeing seized pins
• DuPont Silicone Lubricant — clean, won't attract dirt, ideal for regular maintenance

Note: Avoid graphite powder in wet environments as it can clump. Silicone spray is the best all-around lock lubricant.

Step 3: Relieve Pressure on the Bolt

If the door has shifted and the bolt is pressing hard against the strike plate, the lock won't turn. Push or pull the door slightly to relieve the pressure while turning the key. If this works, the door alignment needs fixing.

Step 4: Thaw a Frozen Lock

For frozen exterior locks in winter:

• Apply hand sanitizer (contains alcohol) to the key and insert it — alcohol lowers the freezing point
• Use a commercial de-icer spray
• Warm the key with a lighter for a few seconds before inserting
• Never pour hot water on a frozen lock — it refreezes and makes it worse

Step 5: Remove a Broken Key Fragment

If a key has broken inside the cylinder, use needle-nose pliers, a broken key extractor tool, or a bobby pin to grip and pull the fragment out. Spray lubricant first to help it slide out.

Step 6: Replace the Lock Cylinder

If lubrication doesn't restore function, the cylinder is worn and needs replacement.

• Mortise/Rim Lock Single Cylinder Replacement — satin brass, includes 5 keys, standard outdoor & indoor use

Prevention

• Lubricate all locks twice a year — spring and fall
• Use silicone spray rather than WD-40 for ongoing maintenance
• Fix door alignment issues promptly to prevent bolt pressure
• Replace worn keys before they break inside the lock