What Is Rekeying and How Does It Work?

Rekeying means changing the internal pins inside a lock cylinder so that a new key operates it and every old key stops working, without replacing the lock hardware itself. It is the fast, cheaper alternative to fitting a whole new lock, and it is the job Adelaide locksmiths do most often after a house sale, a break-up, or a lost key.

How rekeying actually works

Every pin-tumbler lock, which covers most Australian front doors, has a row of spring-loaded pins inside the cylinder sitting at heights matched to one specific key. A locksmith opens the cylinder, pulls the existing pin stack out with a follower tool, and drops in a new stack of pins cut to different heights. That new pattern is what a fresh key is cut to match. The lock body, the faceplate, the strike plate, the deadbolt mechanism, none of it changes. Only the pins and the key change.

On the jobs we see across Adelaide, a single barrel takes a locksmith somewhere between 10 and 20 minutes once they are on site, assuming the cylinder is a standard type. Older or corroded barrels, and anything keyed-alike across several doors, take longer because every cylinder in the set needs the same new pin pattern.

Rekeying versus replacing the lock

The two get confused constantly, so here is the distinction that matters: rekeying changes what opens the lock, replacement changes the lock itself. If the hardware is sound, rekeying gets you the same security outcome (old keys dead, new key working) for a fraction of the cost and time of a full lock swap.

• Rekey when: the lock is in good working order, you just need old keys to stop working, for example after buying a house, ending a share-house arrangement, or a tradesperson handing keys back.
• Replace when: the lock is damaged, worn out, doesn't meet current standards (some older deadlocks fail insurance requirements), or you want to upgrade to a higher security grade.
• Replace when: there was a forced entry attempt and the cylinder or surrounding hardware is compromised.

For a side-by-side cost and decision comparison, rekey vs replace: which costs less walks through both scenarios in more detail.

Does rekeying work on any lock?

Most standard pin-tumbler cylinders, the kind fitted to the overwhelming majority of Adelaide homes, can be rekeyed. A few types cannot, or are not worth it:

• Very old or worn cylinders where the pin chambers are damaged enough that a fresh pin stack will not seat properly.
• Some electronic and smart locks use a different access method entirely (codes, fobs, apps) rather than physical pins, so "rekeying" doesn't apply in the traditional sense, though codes and user credentials can usually be reset.
• Cheap import cylinders sometimes use non-standard pin systems that a locksmith cannot source replacement pins for locally, in which case replacement is simpler than rekeying.

A locksmith can tell within a minute of looking at your cylinder which category it falls into.

What rekeying costs in Adelaide

Rekeying is priced per barrel plus a callout, and it is one of the cheapest jobs a residential locksmith does:

A typical 3-bedroom house has 2 to 4 external barrels (front door, back door, sometimes a side gate or garage entry), so a whole-house rekey usually lands somewhere between $150 and $400 all up, depending on how many barrels there are and whether it's an after-hours job. Keying every barrel alike so one key opens every door is standard practice and doesn't usually add much, if anything, to the per-barrel price.

For a full breakdown of what moves that number up or down, see how much it costs to rekey a house in Adelaide, or run your own numbers through the rekey vs replace calculator to see which option comes out cheaper for your situation.

When people actually get this done

The pattern we see across Adelaide jobs is consistent: rekeying spikes after settlement day for house purchases, after a tenant moves out of a rental, and after a relationship breakdown where one party needs the other locked out. It is also common after tradespeople, cleaners, or previous owners have handed back keys, but you have no way of confirming a copy wasn't kept. In every one of those cases, rekeying solves the actual problem (an unknown number of keys floating around that you can't account for) without the cost of new hardware.

If you're not sure whether your situation calls for a rekey or a full lock change, our rekeying and lock changes page covers both, or get quotes directly.