We’ve all been there: you get home after a long day, fumble for your keys, and realize your deadlock is completely seized, or you’ve lost the only copy of your key with no spare in sight. If calling a locksmith is out of budget or you need access immediately, knowing how to drill out a deadlock is a useful skill that can save you time and money, as long as you do it safely. Most people worry they’ll destroy their door or frame in the process, but with the right tools and a slow, steady approach, you can remove the broken lock without expensive repairs. I’ve done this dozens of times for friends and family over the years, and I’ve picked up plenty of tricks to avoid the most common mistakes along the way.
What You Need Before You Start to Drill Out a Deadlock
You don’t need fancy professional equipment to get this job done, but using the wrong tools will slow you down or cause unnecessary damage. Before you pick up a drill, double check you have all supplies on hand so you don’t have to stop halfway through the process. Always wear safety goggles first—metal shavings from the lock can fly off at high speed and cause permanent eye damage if you’re not protected.
- A corded or high-voltage cordless drill (18V or higher works best; low-voltage drills won’t have enough power to cut through lock metal)
- Two different sizes of cobalt drill bits: a small 1/8-inch pilot bit, and a 1/4-inch bit for widening the hole
- A flat-head screwdriver, hammer, and pair of needle-nose pliers for removing the remaining lock components after drilling
- A can of lubricating spray (like WD-40) to cool the drill bit as you work and reduce friction
- A piece of masking tape to mark your drilling depth and stop you from drilling too far into the door frame
If you don’t have cobalt drill bits, standard titanium bits will work, but they’ll wear out much faster and you may need to stop to replace them mid-job. Never use cheap, low-quality drill bits—they can snap inside the lock, which will make the job far harder to finish. You can pick up a set of cobalt bits for less than $15 at most hardware stores, and they’ll last for years for other home repair jobs too.
Step-by-Step Process to Drill the Lock Safely
Start by positioning the tip of your small pilot drill bit directly in the center of the deadlock’s keyhole. You want to aim for the shear line, which is the point where the lock’s internal pins meet. If you aim too high or too low, you’ll end up drilling through useless metal and wasting time. Apply steady, firm pressure as you drill, and stop every 10 to 15 seconds to spray a small amount of lubricant on the drill bit to keep it cool. Overheating the bit will cause it to dull or break, so don’t rush this step.
Once you’ve drilled through the shear line to a depth of around 1 inch, switch to your larger 1/4-inch drill bit. Widen the hole you just made, going to the same depth as your pilot hole. You’ll feel the drill give way once you’ve cut through all the internal pins, which means the locking mechanism is no longer functional. Don’t drill any deeper than you need to—going too far can damage the internal mounting plate of the lock or the door frame behind it.
After you finish drilling, insert a flat-head screwdriver into the hole you made and turn it the same direction you would turn a key. The deadbolt should slide back easily, and you’ll be able to open the door. If it doesn’t turn, you may not have drilled through all the pins, so go back with the larger bit for 10 to 15 more seconds of drilling. Don’t force the screwdriver to turn, as you can break it off inside the lock and create an even bigger headache.
Common Mistakes to Avoid When Removing a Deadlock
I’ve seen so many people mess up this simple job because they skipped small precautions that end up costing them hundreds in door repairs. One of the most common mistakes is using too much force on the drill. If you push too hard, you can slip and scratch the surface of your door, or snap the drill bit inside the lock. Slow and steady pressure is always better than forcing the drill to go faster. If your drill is struggling to cut through the metal, you’re probably using a low-quality bit or your drill doesn’t have enough voltage.
Another frequent error is not marking your drilling depth before you start. Most deadlocks only require you to drill 1 inch deep to disable the mechanism, so wrap a small piece of masking tape around your drill bit 1 inch from the tip to create a clear stop line. This keeps you from drilling through the other side of the door or damaging the mounting hardware behind the lock, which would make installing a new deadlock far harder. If you’re working on a thicker exterior door, double check the depth of your specific lock model before you mark your bit.
You also don’t want to skip wearing work gloves if you have them. The drill and drill bit can get very hot even with regular lubrication, and you can easily burn your fingers if you touch the bit immediately after drilling. It’s also a good idea to have a new deadlock on hand before you start, so you can replace the broken one right away and don’t leave your home unsecured overnight. If you live in a rental property, check your lease first before drilling a lock, as some landlords require you to use their approved locksmith for repairs.
What to Do After You Drill Out the Deadlock
Once you’re inside, you’ll need to remove the remaining parts of the old deadlock to install a new one. Start by unscrewing the mounting screws on the interior side of the lock, which will let you pull the two halves of the lock apart from each side of the door. If any parts are stuck, use your needle-nose pliers to pull out any remaining metal shavings or broken pin fragments from the mounting hole. Wipe down the area with a damp cloth to remove any leftover metal dust before you fit the new lock.
Take the time to check the door frame and deadbolt strike plate for damage while you’re working. If you accidentally drilled too far and left small scratches, you can fill them with wood putty and paint over them before you install the new lock. Always test your new deadlock multiple times before you close the door to make sure it locks and unlocks smoothly, and that the screws are tightened all the way so it can’t be forced open easily. It’s also a good idea to make 2 or 3 spare keys for the new lock and store them with trusted friends or family members to avoid future lockouts.
If you tried to drill the lock and couldn’t get it to work, don’t keep drilling repeatedly. You’ll only cause more damage to the door, and it will be cheaper to call a locksmith to finish the job than to repair a destroyed door frame later. Most locksmiths charge a flat fee for emergency lockout services, and they can usually be at your home in under an hour if you’re stuck. This is also the better option if you have a high-end smart deadlock, as drilling these can damage internal wiring that’s connected to your home security system.
Knowing how to drill out a deadlock is a handy skill for any homeowner, especially if you ever find yourself locked out with no other way to get inside. You don’t need professional training to do it correctly, as long as you follow the right steps, use the proper tools, and prioritize safety to avoid unnecessary damage. If you take your time and avoid the common mistakes we covered, you’ll be able to remove a broken or seized deadlock in under 30 minutes, and replace it with a new one to keep your home secure. Just remember to always have a spare key made after you install your new lock, so you won’t have to drill out another lock again any time soon.