Rekeying changes the pins inside your existing lock so old keys stop working. Replacing swaps the whole lock body for new hardware. Rekey when the lock is sound and you only need to kill old keys. Replace when the lock is worn, low grade, damaged, or you want a different function or finish.
Most people asking this have just moved house, lost a key, or had a tenant move out. In almost every one of those cases the honest answer is rekey — it costs less and does the same security job. Replacement is the right call less often than people expect, but when it is right, rekeying is money wasted.
What is rekeying?
A pin tumbler lock opens when the pins inside the cylinder line up at the shear line. Rekeying means pulling the cylinder, removing the old pin stack, and fitting a new combination matched to a new key. The lock body, the strike, the finish and the door all stay exactly as they are. Once it is done, every old key is dead.
A rekey takes roughly 15 to 25 minutes per cylinder. Because the hardware stays, you are paying for labour and a small set of pins.
What does replacing a lock involve?
Replacement means removing the existing hardware and fitting a new lock. Sometimes that is a straight swap into the same prep. Sometimes it means drilling a new bore, fitting a different backset, or adjusting the strike and frame. That extra work is why replacement costs more and takes longer.
Rekey vs replace: side by side
| Rekey | Replace | |
|---|---|---|
| What changes | Pins inside the cylinder | The entire lock |
| Do old keys still work? | No | No |
| Typical time | 15–25 min per cylinder | 30–60 min per door |
| Relative cost | Lower | Higher |
| Security grade | Stays the same | Can be upgraded |
| Finish or style | Unchanged | Can be changed |
| Keyed alike possible | Yes | Yes |
| Fixes worn hardware | No | Yes |
When should you rekey?
- You just bought a house and do not know who holds keys
- A tenant moved out
- You lost a key but the lock itself works fine
- A relationship or housemate situation changed
- You want every door on one key and the hardware is decent
- A contractor, cleaner or dog walker had a key
The common thread: the lock is fine, the key situation is not. Rekeying solves exactly that.
When should you replace instead?
- The lock is stiff or sticky, or the key has to be jiggled
- It is a Grade 3 builder-grade deadbolt and you want real security
- The finish is corroded — common near the lake and in older Kenner homes
- There is visible damage from a break-in attempt
- You want a smart lock, a keypad, or a different function
- The bolt does not throw fully into the strike
- It is a no-name brand with no available pinning kit
The salt-air factor in Kenner
Kenner sits between Lake Pontchartrain and the river, and the air carries enough salt to eat cheap hardware from the inside out. On homes near Laketown and the lakefront we see cylinders that cannot be rekeyed at all because the internals have corroded solid. If your key already feels gritty, rekeying is money spent on a lock that is on its way out.
Can you rekey a lock yourself?
Rekey kits exist and work if the brand matches. The catch: kits are brand specific, you need the right key gauge, and losing one tiny spring puts the lock out of action. If you have a single Kwikset deadbolt and patience, it is doable. If you have five doors and want them all on one key, the maths stops favouring DIY quickly.
Does rekeying reduce security?
No. A correctly rekeyed lock is exactly as secure as it was the day it was fitted — same pins, same tolerances, same grade. What rekeying does not do is improve security. A Grade 3 deadbolt rekeyed is still a Grade 3 deadbolt.
What about keyed alike?
Keyed alike means several locks share one key. It is normally done during a rekey and costs little extra once the technician is already there. It only works when the locks use the same keyway — mixing brands usually means replacing some hardware to match.
Not sure which you need?
Tell us the door, the brand if you know it, and what prompted the call. We will tell you which one your situation actually needs — including when the answer is that you do not need us at all. See our indicative pricing or read more about rekeying in Kenner.