— Change your locks after buying a house because you don’t know who still has keys. Rekeying is usually the cheapest and fastest option if locks are in good condition, while full replacement is better for damaged or outdated locks. Most jobs can be done the same day and cost between $40–$100+ for rekeying or hundreds for replacement.
— Change your locks immediately after moving in to eliminate unknown key access—rekey if locks are fine, replace if you want upgraded security.
Yes, you should change the locks when you buy a house because you cannot know how many key copies still exist, and a locksmith can usually do the job the same day within hours. Rekeying a house often costs $40 to $100+, while full lock replacement can cost a couple of hundred dollars, give or take. This guide explains why you should change locks when you buy a house, whether rekey vs replace locks is the better option, what locksmith costs Australian homeowners may expect, and what to do next.
Moving house is already expensive and time-consuming. Lock security is one of the fastest jobs you can handle straight away.
Do You Really Need to Change Locks After Buying a House?
Yes. If you want the direct answer, change locks when you buy a house.
You do not know who still has access. Previous owners may have kept a spare. Agents, cleaners, trades, neighbours, family members, pet sitters, or past tenants may also have had keys copied at some point.
That does not mean anyone plans to come back. It means you are carrying a security risk for no good reason. If you want to start with the wider Jim’s network, you can visit the Jim’s Group homepage or browse the current Services page.
If the locks still work properly, you may not need brand new hardware. In many cases, rekeying solves the problem faster and for less money.
Should You Rekey or Replace Your Locks?
Most buyers choose between rekeying and replacing. The better option depends on the condition of the lock, your budget, and whether you want a security upgrade.
Rekeying Locks (Most Common Option)
Rekeying keeps the existing lock hardware in place. A locksmith changes the internal pins so the old key no longer works, then cuts you a new key.
This is usually the most affordable option. It suits homes where the locks still work well and the main issue is unknown key copies.
Rekeying also makes life easier if you want one key to open multiple doors. If you want to understand how Jim’s structures its service categories and booking options, see Learn About Jim’s Services.
Replacing Locks (When It Makes Sense)
Replacing locks means removing the old lock and fitting a completely new one. It costs more, but it makes sense when the existing lock is damaged, outdated, weak, or difficult to use.
Replacement also suits buyers who want stronger security, upgraded hardware, or a fresh start with all-new cylinders and keys. If the current locks feel worn or unreliable, replacement is often worth it.
| Option | Cost | Best For | Speed |
| Rekeying | $40 to $100+ | Working locks, unknown key copies, same-key convenience | Usually same day, often within hours |
| Replacing | Hundreds of dollars | Damaged locks, outdated hardware, and security upgrades | Often, the same day, depending on hardware and the number of locks |
What Should You Do After Buying a House? (Lock Security Checklist)
Inspect every external lock.
Check the front door, back door, side gate, garage access door, and any sliding doors. Look for loose hardware, worn cylinders, stiff locks, or signs of poor installation.
Decide rekey vs replace locks.
If the locks still work well, rekeying is usually enough. If they are damaged, outdated, or poor quality, replacement often makes more sense.
Call a locksmith early.
Do not leave it for weeks after settlement. The sooner you deal with the locks, the sooner you remove uncertainty around old keys.
Upgrade weak points if needed.
Ask about stronger deadlocks, better strike plates, window locks, or upgraded door hardware. A move is a good time to fix obvious weak points.
Choose your key system.
Decide whether you want all doors on one key or separate keys for separate areas. Most households prefer one key for convenience.
Check who you are hiring.
Use a provider with clear standards, insurance, and customer protection. You can review Why Choose a Jim’s Service and the Jim’s Work Guarantee before booking.
Control spare keys properly.
Only give copies to people who genuinely need them. Keep a simple record so you know who has access.
How Much Does It Cost to Change Locks When You Buy a House?
Here is the quick answer on locksmith cost in Australia that homeowners usually want:
- Rekeying: $40 to $100+
- Replacement: hundreds of dollars
- Final price depends on: number of locks, hardware type, lock condition, and job complexity
Rekeying usually costs less because the locksmith keeps the existing hardware. Replacement costs more because you pay for new lock hardware and installation as well.
If you want a quote through the current Jim’s network, start from the Services page.
Should You Change Locks in a Rental Property?
If you own the rental property, you should make sure the locks provide a reasonable level of security for each new tenant. Many landlords rekey between tenancies because it is cheaper than full replacement and still removes old key access.
If you are the tenant, you usually cannot alter, remove, or add locks without the landlord’s permission. If you do change them with approval, you will usually need to give the landlord a copy of the new key.
Some exceptions can apply in serious safety situations, including family violence. Rental rules vary by state, so check the law that applies where the property is located.
Can You Change Locks Yourself?
Yes, you can change locks yourself, but it is not recommended.
A badly fitted lock can leave the door misaligned, hard to latch, or easier to force. That defeats the whole point of trying to improve security after moving in.
A professional usually does the job faster and more reliably. That matters even more if you want rekeying, stronger security hardware, or one key across several doors. For more background, read 5 Common Questions about Locksmith.
Should All Your Doors Use the Same Key?
For many households, yes. A single key system makes daily life easier.
You carry fewer keys. You waste less time at the door. You also reduce the chance of grabbing the wrong key when you are in a hurry.
A locksmith can usually achieve this through rekeying, as long as the locks are compatible. If you want separate access for a detached office, granny flat, shed, or another occupant, separate keys may be the better option.
The Numbers Behind Changing Locks
- Rekeying cost: $40 to $100+
- Replacement cost: hundreds of dollars
- Time to complete: often same day, usually within hours
- Most common option: rekeying
- Main reason to act: unknown key copies may still be in circulation
These numbers explain why many buyers handle locks early. It is usually one of the fastest security upgrades you can make after moving.
FAQ: Change Locks When You Buy a House
Yes. You should change locks after buying a house because you cannot confirm who still has copies of the old keys. Even one unknown spare is enough reason to act.
Yes. Trust is not the issue. Key control is the issue, and even careful owners may have handed out copies over the years.
In many cases, yes. If the lock hardware still works properly, rekeying removes old key access without the higher cost of full replacement.
Many jobs can be done the same day within hours. Timing depends on how many locks you have and whether you rekey or replace them.
Yes, they can. They may also have given keys to agents, neighbours, relatives, cleaners, or tradespeople at some point.
Usually not compared with other moving costs. Rekeying often starts around $40 to $100+, while full replacement usually runs into the hundreds.
Need Help Finding the Right Security Service?
If you have just bought a house and want to improve your property security, start with Jim’s Group and review the Services page to find the best fit for your needs.
If you want to learn more before booking, visit Learn About Jim’s Services, Why Choose a Jim’s Service, and the Jim’s Work Guarantee.
For related reading, see 5 Common Questions about Locksmith and 3 Ways Locksmiths Can Help With Your Car.