The short version
Rekey when your hardware is in good shape and you just need new keys. Replace when the hardware is worn, low-grade, or you want to upgrade the security level. That’s 90% of the decision in one sentence, but if you want the longer version, here it is.
What rekeying actually does
Rekeying is a five-to-ten-minute job per cylinder. We open the lock, remove the old pins, and install a new pin combination matched to a brand-new key. The lock stays exactly the same, same finish, same feel, same hardware on the door. The only thing that changes is which key turns it.
What replacement actually does
Replacement swaps the entire deadbolt or knob assembly for new hardware. That’s the right call when the existing lock is binding, sticky, scratched up, or simply outdated. It’s also the right call when you want a security upgrade, for example, going from a Grade 3 builder lock to a Grade 1 commercial-grade deadbolt, or moving up to a restricted keyway like Medeco or Mul-T-Lock.
Decision framework
- Just bought the home and want to be sure no one else has keys → rekey
- Lost a key but the lock works fine → rekey
- Roommate or contractor moved out → rekey
- Lock is grinding, sticky, or feels mushy → replace
- Builder-grade hardware on a high-priority entry → replace
- Want a smart lock or restricted keyway → replace
- Lock has visible damage or pry marks → replace
Cost
Rekeying is dramatically cheaper than buying and installing new locks. If your existing locks are in good shape, rekeying gives you the same access-control outcome at a small fraction of the price.
What we usually recommend
Most homeowners benefit from a hybrid approach: rekey the existing exterior locks so old keys stop working, but replace any single failing or builder-grade lock at the same visit. We bring both options on the truck for every appointment so you can decide on the spot. Read more about our rekey service or our lock change service.