How Does Lock Rekeying Work?
Rekeying is how a locksmith makes your old keys stop working without replacing the lock itself. The change happens inside the cylinder, where a handful of small pins decide which key turns the lock. This guide explains what rekeying actually changes, how the process works step by step, and when it is the right choice.
Call Now: (916) 913-5080What Rekeying Changes Inside the Lock
Most home and office door locks are pin tumbler locks. Inside is a rotating core called the plug. Above it sit several stacks of parts: a key pin on the bottom, a driver pin on top, and a spring pressing down. The right key lifts each key pin to an exact height so the split between key pin and driver pin lines up along the shear line - the seam where the plug meets the housing. Only then can the plug turn.
Rekeying replaces the key pins with a set of different lengths matched to the cuts on a new key. The old key no longer lifts the pins to the shear line, so it stops working immediately. The latch, bolt, and door hardware stay untouched.
The Rekeying Process, Step by Step
On a standard deadbolt or knob, rekeying follows the same basic sequence:
- Remove the cylinder from the knob, lever, or deadbolt housing.
- Take off the retainer clip or cam that holds the plug in the cylinder.
- Insert a working key, rotate slightly, and push the plug out with a tube called a plug follower, which keeps the spring-loaded driver pins from launching out of their chambers.
- Dump the old key pins and load new ones sized to the new key's cut depths, one chamber at a time, using a pinning kit and depth chart.
- Reassemble, test the new key, and confirm the old key no longer turns.
Done right, the lock feels exactly as before - it just answers to a different key.
When Rekeying Is the Right Call
Rekeying fits situations where the lock is healthy but the keys are the problem:
- Moving in: you have no idea how many old copies of the key exist.
- Lost or stolen keys: new key pins make every old copy useless.
- Keyed alike: locks that share the same keyway can be pinned to one key, so a single key runs every door.
- Turnover: a roommate, tenant, or employee leaves and access leaves with them.
Rekeying does not fix a worn or sticking mechanism, and it does not raise a lock's security rating - an ANSI Grade 3 lock is still Grade 3 after rekeying. For wear or an upgrade, replacement is the honest answer.
Special Cases and How to Prepare
Not every lock rekeys the same way. Commercial buildings often use small format interchangeable core (SFIC) locks, where a control key pulls the whole core out of the housing so it can be repinned or swapped in moments. Many keypad and smart deadbolts still contain a standard pin tumbler cylinder that can be rekeyed, though some models have no keyway at all. Wafer locks, common in cabinets and mailboxes, use a different mechanism entirely.
Before the visit, find a working key if one exists and note the brand stamped on the lock face or key bow. Skip DIY plug removal - without a follower, the spring-loaded pins scatter and the lock can be left unusable. Call (916) 913-5080, describe your locks and how many doors you have, and confirm whether rekeying fits your situation before anything is scheduled.
Frequently Asked Questions
Do I need a working key to rekey a lock?
A working key helps but is not required. The plug must rotate slightly before it can slide out, and the key is the easiest way to do that. Without one, a locksmith can pick the lock to the shear line first, which adds time but is routine. If your key was lost or stolen, rekeying is the right response - new key pins make every old copy useless.
Is rekeying the same as changing the locks?
No. Rekeying keeps your existing hardware and only swaps the key pins inside the cylinder, so the lock answers to a new key. Changing the locks means removing that hardware and installing new. Rekey when the lock is healthy and you only need to control who holds a key; replace when it is worn, sticking, or a low-grade unit you want to upgrade.
Can every lock be rekeyed?
Most pin tumbler locks - standard deadbolts, knobs, and levers - can be rekeyed. Commercial SFIC locks are built for it: a control key releases the core for repinning or a straight swap. Wafer locks in cabinets and mailboxes use a different mechanism, and a few smart locks have no key cylinder at all. A locksmith can usually identify the type from the brand stamped on the face.
Call (916) 913-5080 about how does lock rekeying work.