How a Lock Works

Before rekeying a lock, it helps to understand how locks work. The type of lock found on most doorknobs and deadbolts is called a pin and tumbler lock. It contains a cylindrical plug that holds a series of pins and springs. The pins are of varying lengths to allow a specifically cut key shape to insert and turn the lock. For this to work, the length of the pins must match the depth of the grooves in the key. To make a lock work with a different key, you need to disassemble the lock, remove the pins, and replace them with ones that match the cuts in the key you wish to use. Let’s learn how.

How to Rekey a Lock

If you have a traditional pin and tumbler lock, rekeying isn’t as difficult as it sounds. First, you’ll need to purchase a rekey kit for the brand of lock you have. The kit should contain various tools to aid in the lock’s removal and a set of different sized pins.

Step 1: Remove the Doorknob

The first step is to remove the doorknob from the door. To do this, you’ll need to align the holes in the cylinder by either turning the knob counterclockwise and holding it or inserting and turning the key a quarter turn to the right. (This step will vary by maker.)

The 5 Best Electronic Deadbolts

Once the holes are aligned, insert the remover tool, press, and pop the knob off, separating it from the shank.

Step 2: Remove the Cylinder

Once you have the knob removed, you need to remove the cylinder from the inside. If your knob has a cap on the back, you’ll need to remove that using an appropriate tool. Then, push the cylinder free from front to back.

Step 3: Take Out the C-Clip

Next, remove the C-clip holding the cylinder in place.

Step 4: Attach Key Plug

Remove the key plug from its housing using the follower tube included in your kit. Attach it to the back of the cylinder and insert the key in the lock. Some locks will require that you turn the key 45-degrees. Now, push the cylinder plug out of the cylinder, leaving the plug follower inside the housing to hold pins and springs in place.

Step 5: Dump the Old Pins

Dump out the pins in the plug. Remove the key and insert the new key.

Step 6: Insert New Pins

Insert new pins as indicated with the kit’s instructions. Make sure they are flush on the top of the plug.

Step 7: Replace the Plug

Replace the plug into the cylinder, slowly pushing out the plug follower as you go. Once inserted, try the key and make sure it turns. Remove the follower and replace the C-clip until it snaps in place.

Step 8: Reattach Knob to Door

Reinsert the cylinder into the knob and reattach the knob to the door.

Step 9: Test the Lock

Once everything is reassembled and feels secure, test the lock.

How to Rekey a Deadbolt Lock

If your deadbolt requires a separate key from your entry doorknob, you can rekey it if they are the same brand. To rekey the deadbolt, remove it from the door and repin as you do a doorknob.

Make sure the bolt is out and remove the screws holding the deadbolt to the door. Remove the cylinder from the housing and the endcap from the cylinder. Take out the retainer pin. Repin as you would for a doorknob, then replace the cylinder into the housing, replace the retainer pin and endcap, and return it to the housing. Re-check that the bolt is out, then reattach the lock to the door.

When to Change Your Door Locks Rather Than Rekey

Maybe you’re unsure if you should rekey your locks or replace them. There are a few instances where replacing them is the better option.

If you’ve lost your key and don’t have a spare, and your knob is locked, you won’t be able to remove the lock to rekey it. You’ll need to replace it. You’re doing a bit of remodeling that includes replacing doors and you want an updated style. That would call for replacing your locks. Rekeying won’t help worn or damaged locks, either. It’s time to replace the locks. If you don’t feel confident rekeying your lock and can’t find someone to do it for you, then you’ll need to change them. To rekey locks to use the same key, all of them must be from the same manufacturer. You can’t rekey a Kwikset lock to use a Schlage key because each maker’s locks have different size holes that will only accept their own keys. So, if all of your doors have different brands of locks, choose the one you want to match, replace the others, then rekey them.