Decisions · updated November 2026
Should I Rekey or Replace My Locks?

What is rekeying?

Most home locks are pin-tumbler locks. Inside the cylinder, small pins of different lengths line up only when the right key is inserted. Rekeying means taking the cylinder apart and swapping those pins for a new set that matches a newly cut key.

The lock body, the handle and the finish stay exactly as they are. The only thing that changes is which key works. Every old key, including copies you never knew existed, stops working.

What does replacing a lock involve?

Replacing a lock removes the existing hardware and installs new hardware: a new knob, lever, deadbolt or smart lock. It is the right choice when the lock itself is the problem, or when you want something the old lock cannot do.

New locks come with new keys, so replacement also stops old keys working. It simply costs more than rekeying when that is all you need.

How do you decide?

How much do rekeying and replacement cost?

Rekeying is priced per cylinder, an estimated $55–$145 per lock each. A knob and a deadbolt on the same door are two cylinders. A house with front and back doors, each with a knob and deadbolt, is four cylinders: roughly $220–$580 before any service call (estimated $50–$100).

Replacing a lock is an estimated $100–$300 per lock, plus the hardware you choose. A new deadbolt installed is about $120–$300, and a smart lock installed about $150–$400. These are estimated market ranges, not confirmed prices.

Can all your locks use one key?

Often, yes. Locks of the same brand and keyway can be rekeyed to the same key, called keying alike. If your doors have a mix of brands, some cylinders may need replacing first, or the locksmith can fit cylinders that match.

Keying alike is popular in Fall River’s two- and three-family houses, where the owner wants one key for the front, back and basement doors while each unit keeps its own key.

Older Fall River locks: rekey or replace?

Many Fall River houses still have locks that are decades old, including mortise locks set into the edge of thick wooden doors. People often assume these must be replaced, but most mortise cylinders can be rekeyed like any other lock, which keeps the original hardware and the look of the door.

Replacement makes sense when the mortise body is broken, parts are no longer available, or you want a modern deadbolt. Fitting new hardware to an old door can take extra work, so get a photo of the door edge to the locksmith before deciding.

What about smart locks and keypads?

A keypad or smart lock is a replacement, not a rekey, because it is new hardware. Once it is installed, though, you rarely need to rekey that door again: you delete a code instead.

Most smart deadbolts still have a key cylinder as a backup. That cylinder can usually be keyed to match your other locks, so one key still opens every door if the batteries ever die.

A checklist after moving into a home

1. Count every exterior lock cylinder, including garage-entry, basement and bulkhead doors
2. Rekey every one so only your keys work
3. Check that each deadbolt extends fully and turns easily
4. Replace any lock that sticks, wobbles or is damaged
5. Add a deadbolt where a door has only a knob lock
6. Decide how many copies you need and who gets them