How Rekeying Works — And When You Actually Need It
Rekeying is one of the simplest and most effective security upgrades you can make. Learn how the process works, when you should rekey your locks, and how it compares to replacing them entirely.
What Rekeying Actually Is
Rekeying is the process of changing the internal pin configuration inside your lock cylinder so that old keys no longer work and new ones do. The lock body itself—the part that's mounted to your door—stays in place. Only the internal mechanisms are altered. This is what makes rekeying such a practical solution: you don't have to remove or replace the hardware that's already working.
When a locksmith rekeies your lock, they remove the cylinder, access the individual pins inside, and rearrange them to match a different key profile. Once reassembled and tested, only the new keys will open that lock. It's straightforward, effective, and typically costs far less than replacing the entire lock.
When You Should Rekey Your Locks
Rekeying becomes necessary in several common situations:
- You've just moved into a new home. You have no way of knowing who has copies of the previous owner's keys. Rekeying immediately gives you full control and security.
- You've lost a key. If there's any chance someone else has found it, rekeying eliminates that risk.
- You've fired an employee or contractor. Even if they return their key, rekeying ensures they can no longer access your property.
- You've ended a relationship. An ex-partner, tenant, or roommate may still have key access. Rekeying removes that concern immediately.
- After a break-in. If there's any possibility that the intruder had access to your keys or made copies, rekeying provides peace of mind.
- Between tenants (for landlords). Professional property managers rekey between every lease to ensure no tenant retains access after moving out.
Rekey vs. Replace — When Each Makes Sense
Both rekeying and replacing locks improve your security, but they serve different purposes and situations.
Rekey your lock if: The lock body is in good condition, still functions smoothly, and you're happy with how it looks and feels. Rekeying is ideal when your only concern is controlling who has keys.
Replace your lock if: The lock is damaged, visibly worn, outdated, or no longer functions reliably. You should also replace if you want to upgrade to a smart lock, high-security lock, or a different style that better matches your home's aesthetic. Replacement makes sense when you need both security and an improvement to the hardware itself.
Many homeowners choose both: they rekey their existing locks immediately after moving in for security, then gradually replace locks as they upgrade their home's security system or style over time.
What the Rekeying Process Looks Like
Rekeying is a quick, straightforward process that typically takes 10–15 minutes per lock. Here's what happens:
- The locksmith removes the lock cylinder from the door by backing out a small retaining pin or screw.
- The cylinder is taken apart to expose the internal pin stack—usually five or six small pins of varying heights.
- The pins are removed and reorganized in a new configuration that matches your new key.
- The cylinder is reassembled and reinstalled into the lock body.
- The new keys are tested to ensure they work smoothly and reliably.
Because rekeying doesn't involve removing the lock from the door—just the cylinder—there's no risk of damaging your door frame or hardware. The process is clean, non-invasive, and you can immediately start using your new keys.
Can You Rekey Locks to Match?
Yes. If you have multiple locks throughout your home and want them all to open with a single key, that's called being "keyed alike." A locksmith can rekey multiple locks of the same brand to the same key profile, so one key opens everything.
This is especially useful for homeowners who have exterior doors, side gates, or storage areas and want the convenience of a master key. It's also a smart choice for rental properties where landlords need a master key for maintenance and emergencies.
Keep in mind that locks must be the same type and brand to be keyed alike. If your exterior doors use different lock manufacturers, they'll need to be either rekeyed separately or replaced with matching locks.