Rekey or Replace Locks? How to Decide

When keys go missing, a housemate moves out or you pick up the keys to a new place, the first instinct is often "I need new locks." Sometimes that is true. Often it is not. Rekeying and replacing both stop old keys from working, but they are different jobs with different costs, and choosing the right one saves money without cutting corners on security.

This guide walks through both options, the questions that decide between them, and the situations we see most often in Bondi Junction and the surrounding eastern suburbs.

The difference in one sentence each

Rekeying keeps your existing lock on the door and changes the pins inside the cylinder so a new key works and old keys do not.

Replacing removes the lock completely and fits a new one, with new keys.

Both give you control of who can get in. Only replacement changes the lock itself — its quality, its style, its condition and its resistance to attack.

Start with one question: is the lock any good?

Almost every rekey-or-replace decision comes down to the condition and quality of the lock you already have. Ask yourself:

• Does the key turn smoothly, without force?
• Does the bolt or latch move fully in and out?
• Is the lock free of visible damage, cracks or heavy corrosion?
• Is it a reasonable-quality lock for the door it protects?
• Do you like how it looks and works?

If the answer to all of these is yes, rekeying is usually the better choice. You keep a perfectly good lock and simply change who has keys.

If any answer is no, replacement is often worth considering, because rekeying would only give you a new key for a lock that has other problems.

When rekeying is the right choice

Moving into a new home

You cannot know how many copies of the keys exist. Previous owners, tenants, agents, cleaners and tradespeople may all have had one. If the locks are in good condition, rekeying every external door on move-in day is quick, affordable and effective. See lock rekeying.

A housemate, tenant or staff member has left

Keys are easy to copy and easy to forget about. Rekeying makes every old copy useless without changing hardware that works perfectly well.

Lost keys

If keys are lost or stolen and could be connected to your address, rekeying promptly removes the risk.

You want one key for several doors

If your locks use compatible cylinders, rekeying can set them all to a single key, which is far more convenient than a ring full of different keys.

When replacement is the right choice

The lock is worn or damaged

A lock that sticks even after the door and strike have been adjusted, a cylinder that wobbles, a bolt that does not throw fully, or a lock body cracked after an attempted break-in all point towards replacement. Sometimes a lock repair solves the problem; if not, a new lock is the answer.

The lock is too basic

Many older homes and rentals have entry locks that were cheap when fitted and are now decades old. A basic spring latch on its own can sometimes be slipped. Replacing it with a quality deadlatch, or adding a deadlock, is a real security improvement that rekeying cannot provide. See lock replacement and our deadlock vs deadlatch guide.

The lock cannot be rekeyed

Some inexpensive locks are not designed to be rekeyed, and some proprietary systems are difficult or impossible to re-pin. In those cases replacement is the only way to stop old keys working.

You want a different style or function

Changing from a knob to a lever, adding a thumb-turn, moving to a keypad lock, or matching new hardware during a renovation all mean replacement.

Corrosion near the coast

In Bondi, North Bondi and other beachside streets, salt air steadily corrodes external locks. A lightly stiff lock can often be cleaned and serviced. A heavily corroded one is usually better replaced with hardware that has a more corrosion-resistant finish.

Comparing the costs

Rekeying is almost always cheaper than replacing the same lock, because you are paying for pins, keys and time rather than a whole new lock plus fitting. The gap is biggest when you have several good-quality locks to change.

However, the cheaper option is only good value if it solves the problem. Paying to rekey a worn-out lock, then paying again to replace it months later, costs more than replacing it once. Our article on locksmith costs in Bondi Junction explains the factors that drive both prices, and lock rekeying costs covers rekeying in more detail.

Mixed answers are normal

In practice, many homes need a combination. A typical move-in visit might look like this:

• Front door deadlock: good condition → rekey.
• Front entrance set: good condition → rekey to the same key.
• Back door: old spring latch only → replace with a deadlatch and add a deadlock.
• Side gate: padlock → replace the padlock with a keyed-alike one.

That approach spends money where it improves security and saves it where the existing hardware is fine.

Special situations

Renting

In NSW, tenants and landlords generally need each other's consent to change locks, and rekeying counts as changing them. Talk to your landlord or agent first. Our guide to NSW lock change rules explains the basics.

Apartments and strata

Apartment entry doors are often fire-rated, and the building may control which hardware can be used. Rekeying an existing approved lock is usually the simplest option. Replacement may need the building manager's approval. See apartment security.

Heritage doors

On original terrace and Federation doors, keeping a serviceable original lock and rekeying or servicing it can preserve the character of the door. Where the old lock cannot be saved, the replacement should suit the period and reuse existing cut-outs where possible. See our heritage door locks guide.

Businesses

For shops and offices, rekeying after staff changes is routine. If the business has frequent turnover or many keyholders, replacing cylinders with a restricted key system can make future changes cheaper and easier. See commercial locksmith.

Warning signs that mean "do not just rekey"

• The key has snapped in the lock before.
• You need to lift, push or pull the door to lock it, even after adjustment.
• The lock shows pry marks or other signs of a break-in attempt.
• The cylinder turns loosely in the door.
• The lock is more than a few decades old and visibly worn.

Any of these deserve a proper look before deciding.

What we do when you call

We ask about the locks, the doors and what has happened. If you can, send a photo or the brand name stamped on the lock. In most cases we can tell you on the phone whether rekeying is likely to be suitable. On site, we check every lock before starting, and if one is not worth rekeying, we tell you and explain the replacement options and cost. You decide.

A quick checklist before you decide

Before calling a locksmith, it helps to work through these points:

1. List every keyed door and gate. Front, back, side, laundry, garage, side gate and any keyed window locks. People are often surprised how many there are.
2. Note which keys you hold. If one key already opens two doors, those locks share a cylinder type and can probably stay keyed alike.
3. Test each lock. Turn every key slowly. Note any that stick, grind or need the door pushed.
4. Look for damage. Pry marks around the strike, a loose cylinder or a cracked escutcheon all suggest replacement.
5. Decide what you want. One key for everything, better security on the back door, or simply peace of mind that old keys are dead.

Bring that list to the call and you will get a clear answer, and an accurate quote, much faster.

Two real-world examples

A rental flat off Bondi Road. New tenants moved in and the agent could not say how many keys previous tenants had cut. The front deadlatch and deadlock were good-quality and working smoothly. With the landlord's consent, both were rekeyed to a single new key. Quick, inexpensive and complete.

A Waverley semi with an old back door. The front locks were fine and were rekeyed. The back door had a decades-old rim latch that could be slipped and a strike held by short screws. That door got a new deadlatch, a deadlock and a reinforced strike plate. Spending more on the weak door and less on the good ones gave the best result for the budget.

Get advice from a Bondi Junction locksmith

Not sure whether to rekey or replace? Call Lizzy Locksmith Bondi Junction on 02 6423 0404, open 7 days, 8:00am – 7:00pm, or send a quote request. We will give you a straight answer and a clear price before any work begins.