You just got the keys to a new place. Somewhere out there is a previous owner, a real estate agent, a contractor, a dog walker, and whoever else picked up a spare over the years. Nobody can tell you how many copies exist — which is exactly why changing the locks is on almost every moving checklist.
The question is how to change them. Rekeying and replacing both solve the “old keys no longer work” problem, but they cost different amounts and solve different secondary problems. Here is how we help customers decide.
What rekeying actually does
Inside every pin-tumbler lock cylinder is a stack of small pins cut to specific heights. The correct key lifts those pins to exactly the right line so the cylinder can turn. Rekeying means taking the cylinder apart and swapping in a different set of pins, so a new key works and every old key stops working.
The lock body, the deadbolt, the strike plate, the finish on your door — all of it stays exactly as it is. You are only changing the combination the cylinder responds to.
When rekeying is the right call
- The hardware is in good shape. The bolt throws smoothly, the key turns without forcing, nothing is loose or corroded.
- You moved into a home with decent locks. No reason to throw away working Grade 1 or Grade 2 hardware.
- You lost a key and want the missing one to stop working.
- A tenant moved out, or you ended a relationship with a contractor or employee who had access.
- You want every door on one key. Multiple locks from the same manufacturer can usually be rekeyed to a single key — a big quality-of-life upgrade if you are currently juggling four.
Rekeying is almost always the cheaper option, and it is faster. Most homes can be done in a single visit.
When you should replace instead
Rekeying does nothing about a lock that was weak to begin with. Replace the hardware when:
- The lock is worn or damaged. Sticking, grinding, a bolt that does not fully extend, visible rust — these are signs the mechanism is at the end of its life.
- You only have a knob lock on an exterior door. A keyed knob without a deadbolt is not adequate security for an entry door.
- The existing hardware is builder-grade. Builders often install the cheapest code-compliant option. Upgrading to a higher grade is a genuine improvement.
- You want features the old lock cannot provide — a keypad, a smart lock, a thumbturn-free double cylinder near glass, or a specific keyway.
- Locks are mismatched brands and you want everything on one key. Mixed manufacturers often cannot be keyed alike without replacing some of them.
The part people forget: the strike plate
A great deadbolt in a weak door frame is still a weak door. Most forced entries are not clever — they are a shoulder or a boot against the door, and the frame splits.
The fix is cheap. A reinforced strike plate secured with three-inch screws that reach past the thin door jamb and bite into the structural stud behind it makes a real difference. Short factory screws only hold the trim. This is one of the highest-value, lowest-cost security upgrades available, and it takes minutes.
A quick way to decide
Ask yourself two questions:
- Is the hardware itself good? If yes, rekey. If no, replace.
- Do I want something the current lock cannot do? If yes, replace — even if the old lock still works.
In a lot of houses the answer is a mix: rekey the three solid deadbolts, replace the tired back-door knob lock, and put everything on one key. That is a normal, sensible outcome and usually the best value.
Do it before you unpack
Whichever route you take, do it early — ideally the week you take possession. It is a small job that removes a genuine unknown, and it is far easier to schedule before the house fills up with boxes.
If you are not sure which of your locks are worth keeping, we are happy to take a look and tell you straight. Sometimes the honest answer is that your existing hardware is better than what a replacement would give you.