How to Rekey a Lock

Written by
Lee Wallender
Lee has over two decades of hands-on experience remodeling, fixing, and improving homes, and has been providing home improvement advice for over 12 years.
Learn about The Spruce's Editorial Process
Lee Wallender
Updated 07/01/20
Rekey a Lock

Bill Oxford / Getty Images

Overview
  • Working Time: 90 mins
  • Total Time: 2 hrs
  • Yield: 3 locks
  • Skill Level: Beginner
  • Estimated Cost: $10 to $20

When you need your house door locks rekeyed, you can always buy entirely new locks and install them. But this is an expensive solution to a simple problem. This fix wastes locks and doorknobs simply for the sake of obtaining new keys. Plus, if you need to rekey multiple locks, you end up with multiple keys. The best solution is to rekey your locks.

Rekeying a lock is a common task for a locksmith. Homeowners may not know that they can rekey their own locks by themselves. Rekeying your own locks saves considerable money, especially when you need to rekey multiple locks. Plus, if you like new challenges, rekeying a lock can be an inexpensive project that helps you learn how locks operate.

How a Lock Works

Door knobs, door levers, and deadbolts with keyed locks usually have two sets of pins set within a plug: driver pins and key pins. Pushing a key into the plug forces the pins up and down at varying heights.

Attached to springs, the driver pins are all the same length. These will not be changed out when rekeying the lock. The other set, the key pins, are of different lengths and will be removed and replaced during the rekeying process.

When a lock is locked, the two sets of pins act as obstacles, preventing the plug from rotating. When a key is pushed into the plug, it contacts the key pins. The key pins, in turn, contact the driver pins and bring them within alignment at the shear line, allowing the plug to turn and thus open the lock.

How Rekeying a Lock Works

When you rekey a lock by yourself, you will need to purchase a rekey kit that is specific to your brand.

You will receive a number of keys (often between three and six keys), all identically cut. A set of pins comes with the kit, numbered or color-coded to identify their positions in the plug.

The new keys correspond to the new pins. In most cases, all other pieces of the lock stay the same. A few simple tools are usually included with the kit.

Is It Legal to Rekey a Lock?

Generally, as long as you own the property to which the lock and key belong, you may rekey the lock, as long as no other factors are involved. One notable set of factors may be landlord-tenant laws that limit or prohibit rekeying when the renter is still living on the property. Similarly, as a tenant, it is unlikely that you may rekey a lock without the landlord's permission.

As these can be complicated issues, consult a qualified attorney about this or any other question about the legality of rekeying your lock.

When to Rekey Your Lock

Locks are most commonly rekeyed when one or more keys have been lost or stolen. Rekeying the lock or locks ensures that someone who might find the key—and can match the key to its lock—cannot open the lock and enter the home.

Besides protecting against potential thieves, locks are often rekeyed when renters, housemates, spouses, or partners leave the home but still have a key or may have duplicated the key.

What You'll Need

Equipment / Tools

  • Original key for your lock

Materials

  • Rekey keying kit for your lock

Instructions

  1. Remove the Exterior Knob

    Insert the key and turn it a quarter-turn to the right. Use the remover tool included in the kit to press the clip that allows you to remove the knob from the shank.

  2. Remove the Cylinder Lock From the Knob

    Turn the key a quarter-turn back and remove the key. Remove the cylinder.

  3. Push Off the Clip Ring

    The kit will have a tool that helps you remove a C-shaped clip from the cylinder lock.

  4. Remove the Key Plug From the Key Housing

    The kit will have a pusher device that helps you to push the key plug from the key housing.

  5. Remove the Old Pins

    On a clean, flat surface, drop the old pins from the plug. Push them to the side so they don't get mixed in with the new pins.

  6. Insert the New Key

    Remove the old key and insert the new key.

  7. Insert the New Pins

    The kit should have a chart that shows the new pins' order. Follow this chart and insert the new pins, using the included tweezers.

    Always be sure that the rounded or pointed (not flat) end of the pins are facing the key. Otherwise, the lock will not turn.

  8. Insert the Key Plug Into the Housing

    Make sure the pins are flush at the top. With the key still in place, slide the key plug back into the housing.

  9. Snap on the Clip Ring

    With the included tool, snap the clip ring back on the cylinder.

  10. Insert the Cylinder Lock Into the Knob

    Reinsert the cylinder into the doorknob from the back.

  11. Insert the Knob on the Shank

    Slide the doorknob back onto the shank. Insert the key and turn it, allowing you to continue inserting the knob on the shank.

Tips For Rekeying a Lock

  • Rekeying a lock involves handling tiny pins. If you have poor vision, you may need to use glasses or a magnifying lens for the procedure.
  • Do not throw away the old key until you are certain that the new keys work with all of the rekeyed locks.
  • If you are rekeying multiple locks, you can expedite the process by doing all of them at once. But be sure to keep all of the pins separate. You want to make sure that a specific group of pins stays with its own lock.

When to Call a Professional

You will need to call a locksmith if all of the keys are missing. At least one working key is required to rekey a lock by yourself.