How to Rekey a Door Lock Without a Locksmith: Save Money DIY

When you move into a new home, lose a key, or end a relationship with someone who had a copy of your key, rekeying your locks is essential for security. A locksmith typically charges $50–$200 to rekey a house, but you can do it yourself for under $15 with a rekeying kit. The process takes about 10 minutes per lock once you know what you're doing.

What Does Rekeying a Lock Mean?

Rekeying changes the internal pins inside the lock cylinder so that a new, different key operates the lock. The lock hardware itself stays in place — you're only changing the tiny spring-loaded pins that match the cuts on your key. After rekeying, the old key will no longer work.

Rekeying vs Replacing a Lock

People often confuse these two options:

• Rekeying keeps the same lock and hardware but changes the key. Cost: $3–$15 per lock (DIY). Best when your existing locks are in good condition and you just need to change who has access.
• Replacing means removing the entire lock and installing a new one. Cost: $25–$200 per lock. Necessary when the lock is worn out, damaged, or you want a different style or security grade.

If your existing locks are a decent quality (Grade 2 or better), rekeying is almost always the smarter choice.

When Should You Rekey Your Locks?

• You just moved into a new home or apartment (you don't know how many copies of the key exist)
• You lost a key or had one stolen
• A roommate, tenant, or ex-partner still has a key
• A contractor or service worker was given temporary access
• You want all your locks to use the same key (keyed alike)
• You bought the house from a bank (foreclosure) — multiple realtors may have had lockbox access

What You'll Need (Rekeying Kit)

Major lock manufacturers sell brand-specific rekeying kits:

• Kwikset SmartKey: Kwikset locks with SmartKey technology can be rekeyed in seconds with just the current key and the new key — no disassembly needed. A SmartKey rekey tool costs about $3.
• Schlage Rekey Kit: Schlage sells a rekeying kit (about $10–$15) that includes new pins, springs, a plug follower, and tweezers. This works on all Schlage pin-tumbler locks.
• Universal Rekeying Kit: For other brands, you can buy a universal kit with various pin sizes, a plug follower, and tools. These cost $10–$20.

You'll also need:

• The current working key (critical — you cannot rekey without it unless using SmartKey's reset tool)
• The new key you want the lock to work with
• A small flathead screwdriver
• Good lighting and a clean, flat workspace

Step-by-Step Rekeying Process (Kwikset SmartKey)

Kwikset's SmartKey system is by far the easiest to rekey — no tools or disassembly required.

1. Insert the current working key and turn it 90 degrees clockwise (to the 3 o'clock position).
2. Insert the SmartKey tool (a small flat tool included with the lock or sold separately) into the SmartKey hole — a small slot next to the key cylinder. Push it in firmly until you feel it depress.
3. Remove the current key.
4. Insert the new key all the way in.
5. Turn the new key back 90 degrees counterclockwise to the 12 o'clock (vertical) position and remove it.
6. Done. The lock now works with the new key. The old key will no longer function.

The entire process takes about 15 seconds. Kwikset SmartKey locks can be rekeyed virtually unlimited times.

Step-by-Step Rekeying Process (Schlage and Standard Pin-Tumbler Locks)

1. Remove the lock from the door. Remove the two mounting screws on the interior side and pull off both halves. Remove the lock cylinder from the housing.
2. Remove the cylinder plug. Insert the current key and turn it slightly (just enough to align the plug's retainer clip). Use the clip removal tool to depress the retainer clip while turning the plug with the key. The plug (the part the key goes into) will slide forward out of the cylinder housing.
3. Use the plug follower. As you remove the plug, immediately push the plug follower (a cylindrical tool the same diameter as the plug) into the housing from behind. This keeps the driver pins and springs from falling out. Do not let any springs escape.
4. Dump the old pins. With the plug removed, turn it upside down and the old key pins will fall out. There are typically 5 or 6 pins.
5. Insert the new key into the plug.
6. Insert new pins. Using tweezers, place the correct new pins into each pin chamber. Each pin must sit flush with the top of the plug when the new key is inserted. The rekeying kit includes a decoder or chart to match pin sizes to key cuts.
7. Reassemble. Slide the plug back into the cylinder housing while simultaneously removing the plug follower. The retainer clip should snap back into place. If it doesn't click, the plug isn't fully seated — push it in further.
8. Test the lock before reinstalling it on the door. The new key should turn smoothly. The old key should not turn at all.
9. Reinstall the lock on the door and test again.

Rekeying to Match Multiple Locks (Keyed Alike)

One of the best reasons to rekey is to make all your exterior locks work with a single key. To do this:

1. Choose one key as your master (either an existing key or buy a new blank cut at the hardware store)
2. Rekey each lock to match that key's pin configuration
3. All locks on the same key brand/keyway must match — you can't rekey a Schlage lock to a Kwikset key or vice versa

With SmartKey Kwikset locks, this is trivially easy — just rekey each lock with the same new key. For Schlage, you'll need to decode the master key's cuts and use the matching pins for each lock.

Common Mistakes When Rekeying

• Losing springs. When removing the plug, springs can shoot out if the plug follower isn't inserted quickly enough. Work over a towel to catch any escapees.
• Wrong pin sizes. Each pin must match the corresponding key cut exactly. Even one wrong pin means the key won't turn. Double-check each pin with the decoder chart.
• Mixing up pin order. Pins are sized for specific positions. Pin #1 goes in the first chamber (nearest the key tip), and so on.
• Forgetting the retainer clip. If the retainer clip doesn't re-engage, the plug can slide out during use. Make sure you hear or feel the click.
• Not having the current key. You must have a working key to remove the plug. Without it, the pins don't align and the plug won't come out. If you've lost all keys, you'll need a locksmith or must replace the lock.

When to Call a Professional

• You don't have any working key for the current lock
• The lock is a high-security model (Medeco, Mul-T-Lock) requiring specialized tools
• You need to rekey many locks and don't have the time or patience
• The lock mechanism is damaged or corroded internally

Cost Comparison: DIY vs Locksmith

For a typical house with 3–5 exterior locks, DIY rekeying saves $70–$175 versus calling a locksmith.

Frequently Asked Questions

Can I rekey a lock to match an existing key? Yes, as long as the existing key uses the same keyway (brand). You can rekey a Schlage to match any other Schlage key, for example.

Does rekeying void the lock warranty? No, rekeying with manufacturer-approved kits does not void the warranty. In fact, Kwikset specifically designs their SmartKey locks for user rekeying.

How many times can a lock be rekeyed? Virtually unlimited times. The pins and springs may wear after many cycles, but the lock cylinder itself doesn't degrade from rekeying.

Can I rekey a smart lock? If the smart lock has a physical key cylinder (most do, as a backup), yes, you can rekey the mechanical portion. The electronic codes are separate and changed through the lock's app or keypad.