How Lock Rekeying Works: A Plain-English Explanation for Inland Empire Homeowners

"I want to rekey my locks" is one of the most common requests we receive at Lock Busters across the Inland Empire. But for many homeowners, rekeying is a somewhat mysterious process — they know they want it done but are not entirely sure what it means.

This guide demystifies rekeying completely. What it is, exactly how it works at a mechanical level, when it makes sense versus replacement, and what you can expect during the service.

What Is a Lock, and How Does It Work?

To understand rekeying, you need a basic understanding of how a pin-tumbler lock works — the type used in the vast majority of residential deadbolts and door knobs across the Inland Empire.

Inside your lock cylinder is a series of vertical chambers (usually 5 or 6). Each chamber contains a pair of spring-loaded pins:

• Key pin (lower pin) — contacts the key when inserted
• Driver pin (upper pin) — sits above the key pin, pressed by a spring

When no key is inserted, the driver pins cross the "shear line" — the boundary between the rotating cylinder and the fixed housing — preventing the cylinder from turning.

When the correct key is inserted, the cut pattern lifts each key pin to a different height. The cuts are precisely calibrated so that every key pin rises to exactly the shear line, pushing each driver pin fully above it. With all driver pins above the shear line, the cylinder rotates freely. The lock opens.

The wrong key lifts pins to incorrect heights. Some driver pins remain below the shear line, blocking rotation. The lock stays locked.

What Rekeying Actually Changes

Rekeying replaces the key pins (the lower set) with pins of different heights. The new pin heights correspond to a new key cut pattern.

After rekeying:

• The original key's cuts no longer align with the shear line at any chamber
• The new key's cuts align precisely across all chambers
• The hardware itself — the cylinder housing, the bolt mechanism, the external hardware — is completely unchanged
• The security level is identical to a brand-new lock of the same model

Rekeying takes approximately 20 minutes per lock. It requires no special installation and leaves the door hardware exactly as it was.

The Step-by-Step Rekeying Process

Here is exactly what happens during a professional rekey service:

Step 1 — Remove the lock cylinder from the door. For a deadbolt, this typically means removing a tailpiece or set screw and withdrawing the cylinder. For a knob lock, the knob assembly is removed to access the cylinder.

Step 2 — Use a plug follower tool to remove the cylinder plug. The plug is the rotating inner portion. A specialized tool holds the spring-loaded pins in place during removal.

Step 3 — Remove the existing key pins. Using a rekeying kit (brand-specific — Schlage, Kwikset, Defiant, and others all use slightly different pin sizes and spacing), the existing key pins are identified and removed.

Step 4 — Decode the new key. If you are providing a specific key to match (for example, a house key you want all locks to match), the locksmith reads the cut depths on that key and selects the corresponding pin heights from the rekeying kit.

If no reference key is provided, the locksmith selects a new pin combination, cuts new keys to that combination, and provides them to you.

Step 5 — Install the new key pins. New pins of the correct heights for the new key pattern are inserted into each chamber.

Step 6 — Reassemble and verify. The cylinder is reassembled, reinstalled in the lock, and tested with both the old key (must not turn) and the new key (must turn and operate the bolt smoothly).

When Rekeying Is the Right Choice

Rekeying is the correct service when:

• You have moved into a new home (resale or new construction)
• You have given out copies and want a clean key control situation
• You have ended a relationship with someone who had a key
• A key was lost or stolen and you want to neutralize it
• You want all your doors to work on a single key without replacing hardware
• Your existing lock hardware is in good condition and meets your security needs

When Full Replacement Makes More Sense

Replacing the lock entirely is better when:

• The existing hardware is worn, binding, or mechanically compromised
• You are upgrading from Grade 2 or below to Grade 1 security hardware
• You want to add smart lock functionality
• The lock shows signs of tampering, picking, or drilling attempts
• You are doing a general home renovation and want matching new hardware throughout

All Locks to One Key: The Convenience Rekey

One of our most popular services in the Inland Empire is rekeying all exterior locks to a single key. This is called a "master key" or "single key" rekey.

Instead of carrying separate keys for the front door, back door, side entry, and garage access door — all matching hardware within the same brand family can be rekeyed to the same key cut pattern. One key for everything.

Limitations: This works within the same lock manufacturer family. Schlage to Schlage, Kwikset to Kwikset. Cross-brand rekeying to a single key is not mechanically possible due to different cylinder specifications.

What a Professional Rekey Service Costs in the Inland Empire

Lock Busters residential rekeying rates:

• Service call fee: $55–$75
• Per lock rekey: $25–$45
• 3-bedroom home (5–6 exterior locks): $200–$345 all-in
• 4-bedroom home (7–8 exterior locks): $265–$435 all-in
• Single-key matching: Included — no additional charge

All new keys are cut on-site. We provide the exact number of key copies you request. Service is completed in a single appointment.

Call (909) 935-8844 for same-day rekeying service across all Inland Empire cities.