Deadbolt Lock Repair for Sticking, Grinding and Loose Locks

The lock is often not what's broken

When a deadbolt fights you, the natural guess is that the lock has failed. On most repair calls it hasn't. The bolt is rubbing a strike that has shifted, the door has dropped on its hinges, or years of grit and the wrong lubricant have built up in the cylinder.

That matters for your wallet. A deadbolt lock repair that corrects the strike or cleans the cylinder costs far less than new hardware, and it keeps a good lock on the door. Replacement only earns its place when the lock itself is worn, weak or damaged.

A useful benchmark comes from the residential deadbolt standard. BHMA's public summary of A156.40 says a Grade A lock must retract its bolt with no more than 9 inch-pounds of torque, which is a light turn. If yours takes a firm grip and a wrist twist, something is adding friction that the lock was never designed to carry.

Symptoms we fix, and what usually causes them

The table below matches each complaint to its usual cause. Homeowners who want to try the basic checks themselves first can follow our deadbolt won't lock troubleshooting guide. This page covers what happens when those checks don't solve it.

A bolt that sticks or drags

The quickest test is to throw the bolt with the door open. If it moves freely, the lock is fine and the problem lives in the strike or the door. Houses settle, hinge screws loosen and the bolt starts catching the top or bottom edge of the strike opening.

Our Deadbolt Fixers technicians find the exact contact point, then move or open up the strike so the bolt clears it. If the door has sagged, the hinges get attention first, because moving the strike without fixing the sag only lasts until the next season.

Grinding and scraping

Grinding is metal on metal, and it rarely fixes itself. On the strike side it wears a groove into the bolt and loosens the plate. Inside the lock, it usually means dirt in the bolt housing or a part that has started to wear.

A bolt that won't fully extend

A residential deadbolt typically throws a 1-inch bolt, and it needs room to get there. Schlage's B-Series instructions call for a strike hole at least 1-1/4 inches deep. Builders and DIY installers sometimes drill shallower, which leaves the bolt short of full throw and easier to push back.

A loose or slipping thumb turn

The inside half of a deadbolt is held by two through-bolts that pass into the outside cylinder. When they loosen, the thumb turn wobbles and the tailpiece no longer engages the bolt cleanly. Sometimes tightening is enough. If the screw posts are stripped or the tailpiece is twisted, we replace those parts.

A key that has become hard to turn

Gradual stiffness over months or years points to wear. Schlage's own troubleshooting guide says that when a key sticks or turns hard after the lock has been in use for a while, a replacement cylinder is required.

Before we replace anything, we rule out the key and the lubricant. Schlage's service manual names keys worn past factory specification, and copies made from copies, as common reasons a lock stops working well. It also warns that too much powdered graphite can pack the cylinder and stop the pins moving freely. A key that has actually snapped is a different job, covered on our broken key extraction page.

How a deadbolt lock repair visit runs

Every deadbolt lock repair we do follows the same order, so nothing gets missed and you approve the cost before work starts.

1. Isolate the fault. We operate the bolt with the door open, then closed, then with the key from outside. That separates lock problems from door problems.
2. Inspect the door. Hinge screws, door sag, the strike position and the depth of the strike pocket.
3. Inspect the lock. Through-bolts, thumb turn, tailpiece, cylinder and the key you use every day.
4. Quote the fix. You get a price for the repair and, if it's close, the price of replacement alongside it.
5. Repair and test. We test every key you use, from both sides, with the door closed.

Smart locks get the same treatment. Schlage lists misalignment between bolt and strike as a common cause of the "lock jammed" alert in its app, so a motorized deadbolt that keeps reporting jams usually needs door work, not a new motor. For full retrofits, see smart deadbolt installation.

Repair it or replace it?

Work through these four questions in order. The first "replace" answer you hit is usually the right call.

Repair or replace your deadbolt

1. Q1Does the bolt move freely when the door is open?

   YesThe lock is likely sound. Repair the strike or door fit.

   NoThe fault is inside the lock. Go to the next question.

2. Q2Is there forced-entry damage: pry marks, a drilled or twisted cylinder, a bent bolt?

   YesReplace the lock and check the strike and jamb for damage.

   NoGo to the next question.

3. Q3Has the key grown stiff gradually, even with a key cut to code?

   YesThe cylinder is worn. Replace the cylinder and keep the rest of the lock.

   NoGo to the next question.

4. Q4Are you happy with the lock's grade, finish and features?

   YesRepair it. Cleaning, parts and adjustment will restore it.

   NoReplace it, since a new lock fixes the fault and upgrades the door in one visit.

When the answer lands on replacement, our deadbolt replacement service fits a new lock in the existing holes in most cases. If a repaired door still feels weak at the frame, ask about reinforcing the strike plate during the same visit. BHMA notes that real-world performance depends on installation and the door and frame, not just the lock's lab rating.

What moves the price of a repair

A deadbolt lock repair is quoted on what the fix involves, not a flat menu. These factors decide the number:

• Door work versus lock work. Strike and hinge adjustments need time but few parts. Cylinder or bolt replacement adds hardware.
• Parts availability. Common residential brands are carried on the van. Older or uncommon locks may need parts ordered.
• Timing. After-hours visits cost more. In Locksmith Ledger's 2024 reader survey, which it describes as not scientific, average labor was $104 per hour regular and $151 per hour after hours, with a $94 average service call. These are national averages and vary by location.
• Other jobs at the same visit. Rekeying or reinforcing while we're there shares the trip charge.

For how full quotes are built across every deadbolt job, see our guide to deadbolt costs.

Before you book: write down three things

Tell us whether the bolt behaves differently with the door open, whether the problem changes with the weather, and which key you use. Those three answers let us arrive with the right strike, cylinder or parts, and they often turn a two-trip deadbolt lock repair into one visit.