One of the most common questions we get at Northcoast Locksmiths is: "Do I need new locks, or can I just get them rekeyed?" It's a good question — and the answer depends on why you're asking it and the condition of your existing locks. In many situations, rekeying is the smarter and more cost-effective choice. In others, replacement is the right call. Here's how to tell the difference.

What Rekeying Actually Is

A lock cylinder contains a row of spring-loaded pin stacks. Each stack has two pins of different lengths. When the correct key is inserted, it pushes each stack to a precise height, aligning all the pins at the shear line — the point where the cylinder can rotate and the lock opens. The specific combination of pin heights is what makes your key unique to your lock.

Rekeying means a locksmith removes the cylinder, replaces the driver pins inside it with a different set of heights, and cuts you new keys to match. The external hardware — the lock body, the handle, the deadbolt mechanism — stays exactly as it was. Only the internal pin configuration changes, meaning all previous keys are permanently deactivated.

It's a relatively quick job. An experienced locksmith can rekey most standard cylinders in 10–20 minutes per lock.

When to Rekey

Rekeying makes sense when your existing locks are in good mechanical condition and you simply need to invalidate old keys. The most common scenarios:

  • Moving into a new home — You have no idea how many keys are floating around from the previous owner, real estate agents, tradespeople or previous tenants. Rekeying all external locks immediately is standard practice and strongly recommended.
  • Lost or stolen keys — If your keys have gone missing and you can't account for them, rekeying is faster and cheaper than full replacement.
  • Change of tenants — Landlords should rekey between tenancies as a matter of routine. It's inexpensive and removes any question about key control.
  • Relationship breakdown — If a partner, housemate or family member moves out and you're not confident all keys have been returned, rekeying restores full control.
  • Keying alike — If you have multiple locks with different keys, rekeying can key them all to a single key, which is a genuine convenience upgrade.
Tip

When you move into a new property anywhere on the Sunshine Coast, treat rekeying as a non-negotiable part of the moving-in process — not an optional extra. The cost is minimal compared to the peace of mind it provides.

When to Replace

Full lock replacement is the better choice when the existing hardware has problems that rekeying won't fix:

  • Worn or damaged lock mechanism — If the cylinder is stiff, the bolt is sluggish or the lock has physical damage, rekeying a worn lock just gives you new keys to a faulty lock. Replacement is the right answer.
  • Security upgrade — If you currently have a Grade 2 or Grade 3 lock and you want to upgrade to Grade 1 high-security, you need new hardware. You can't rekey a low-grade lock into a high-security one.
  • Mismatched or mixed brands — If you're trying to establish a keyed-alike system across multiple locks of different brands, replacement with matching hardware is often cleaner and more reliable than trying to match pin profiles across brands.
  • After a break-in — If a lock has been forced, picked or damaged during a break-in attempt, replace it. The internal components may have been stressed or damaged in ways that aren't visible.
  • Very old hardware — Locks more than 20–25 years old on external doors in a Sunshine Coast hinterland environment are likely showing significant wear. The cost-benefit of rekeying old, corroded hardware rarely stacks up.

Cost Comparison

For the Nambour area, typical pricing as a rough guide:

  • Rekeying a single cylinder: approximately $50–$90 per lock (plus callout)
  • Rekeying a full home (3–4 external locks): approximately $150–$280 all-in
  • Replacing with a quality Grade 1 deadbolt (supply and install): approximately $200–$350 per lock depending on brand and hardware

For a standard hinterland home where the locks are in good condition, rekeying will typically cost 30–60% less than full replacement. For a home that needs security upgrades, the premium for new high-security hardware is worth paying.

The DIY Risk

Rekey kits are sold at hardware stores and look straightforward on paper. In practice, rekeying requires a pinning tray, the correct follower tool, and knowledge of which pin sizes correspond to which key cuts. Errors — wrong pin depth, a spring that isn't seated, a pin dropped into the cylinder body — can leave you with a lock that doesn't function. Having a locksmith undo a DIY rekeying mistake typically costs more than having the job done professionally from the start. Unless you have experience with lock mechanisms, the professional route is the better value.