tips 3 December 2025

Is Getting a Spare Car Key Worth It? The Maths Says Yes

Think a spare car key is an unnecessary expense? This article breaks down the real numbers — comparing the cost of a spare key now versus an all-keys-lost emergency later.

CL

Car Locksmith Sydney

3 December 2025

Is Getting a Spare Car Key Worth It? The Maths Says Yes

Most people never think about a spare key until they are standing next to a locked car with empty pockets. The realisation hits hard. You are now in an “all-keys-lost” situation.

We see this panic every day across Sydney. This scenario is significantly more expensive and time-consuming than simply having a backup ready.

Our team has crunched the numbers to show you the real cost difference. Getting a spare car key replacement made is one of the smartest financial decisions a driver can make.

The Two Scenarios

We categorise these situations into two distinct buckets for our customers.

Scenario A: You proactively get a spare key made while you still have your original.

Scenario B: You lose your only key and require an emergency all-keys-lost replacement.

The price gap between these two options is often shocking to vehicle owners.

The Numbers: Spare Key vs All-Keys-Lost

We have updated these figures to reflect current market rates in Sydney for 2026.

For a Standard Transponder Key (e.g., 2020 Toyota Corolla)

ScenarioCost (AUD)
Spare key (while you have the original)$160 - $220
All-keys-lost emergency replacement$380 - $550
Difference$220 - $330 saved

For a Remote Flip Key (e.g., 2021 Ford Ranger)

ScenarioCost (AUD)
Spare key (while you have the original)$220 - $300
All-keys-lost emergency replacement$450 - $650
Difference$230 - $350 saved

For a Smart Proximity Key (e.g., 2023 Mazda CX-5)

ScenarioCost (AUD)
Spare key (while you have the original)$280 - $380
All-keys-lost emergency replacement$550 - $900
Difference$270 - $520 saved

For a Premium Smart Key (e.g., 2022 BMW 3 Series)

ScenarioCost (AUD)
Spare key (while you have the original)$400 - $600
All-keys-lost emergency replacement$800 - $1,500
Difference$400 - $900 saved

In almost every case, the spare key costs roughly 40% to 60% less than an all-keys-lost replacement.

Infographic comparing the cost of getting a spare car key proactively versus paying for an all-keys-lost emergency replacement

Why Is All-Keys-Lost So Much More Expensive?

We often get asked why the price jumps so drastically when the last key is gone.

The answer lies in the technical labor required. When you have at least one working key, a locksmith can:

  • Clone the data: We use the existing key’s transponder chip as a “master” to copy data to the new key.
  • Bypass security blocks: The working key acts as a handshake with the car’s computer to authorise a new key.
  • Finish quickly: The entire process usually takes 20 to 45 minutes.

When all keys are lost, the process changes entirely. We must:

  1. Gain entry manually: This requires specialised tools (like Lishi picks) to unlock the vehicle without damage.
  2. Decode the lock: We have to read the wafer depths inside the door lock to determine the physical cut of the key.
  3. Reset the immobiliser: Australian standards for modern cars require us to wipe the car’s computer (ECU) clean of old keys before adding new ones.
  4. Extract pin codes: We often need to pull the dashboard apart or connect to the OBD2 port to extract the vehicle’s security PIN code from the Body Control Module (BCM).

This extra complexity turns a quick job into a 60 to 120-minute operation.

The Hidden Costs of Losing Your Only Key

The locksmith fee is just the tip of the iceberg.

We have seen customers face a cascade of other expenses when they are stranded.

Towing Costs

If your car is in a hard-to-access spot or a clearway, you might need a tow.

In New South Wales, maximum towing fees are regulated, but they are still high. A standard tow in the Sydney metro area often starts at $268 for the first 10km. If you are stuck in a parking station with a low ceiling, you will need a specialised recovery vehicle, which costs even more.

Lost Income

Being unable to drive means missed opportunities.

A single day off work for a tradesperson or contractor can cost upwards of $400 to $500. Even for office workers, burning a day of annual leave to wait for a locksmith is a financial loss.

Rideshare and Taxi Fares

You still need to get around while your car is grounded.

A return Uber trip from a suburb like Parramatta to the Sydney CBD during peak hours can easily cost $90 to $110. Do this for two days while sorting out your key, and you have added another $200 to the bill.

After-Hours Premiums

Emergencies rarely happen at 10:00 AM on a Tuesday.

They happen on Friday nights or Sunday mornings. Most mobile services, including ours, charge an after-hours surcharge ranging from $80 to $180 depending on the time and location.

The Full Cost Comparison

Let’s look at a real-world example for a Sydney driver with a 2023 Hyundai Tucson smart key.

With a Spare Key

ItemCost
Spare key (made proactively)$320
Lost primary key — use spare$0
Get replacement for lost key (at your convenience)$320
Total cost$640

Without a Spare Key

ItemCost
No spare key$0
Lost only key — emergency locksmith$750
After-hours surcharge (Saturday night)$120
Uber to work Monday morning$55
Uber home Monday evening$55
Total cost$980

The spare key saves $340 in direct costs. This does not even account for the stress of being stranded on the side of the road.

A relieved driver using their spare car key after losing their primary key showing the value of having a backup

When Is the Best Time to Get a Spare Key?

We tell all our customers the same thing: the best time is right now.

Waiting until you “have time” usually leads to forgetting. Consider these specific trigger points:

  • The moment you buy a used car: Checks show that over 40% of used cars sold privately in NSW come with only one key. Negotiate the cost of a spare into the purchase price.
  • When booking a service: If a locksmith is already on-site for a house lock or another car, ask for a deal. We can often offer a discount on a second key because the travel time is already covered.
  • Before a road trip: Getting stuck in regional NSW without a key is a nightmare. Rural locksmiths may be hundreds of kilometres away, and towing costs can hit four figures.

Where to Keep Your Spare Key

A spare key inside the locked car is not a spare key.

We recommend these secure locations:

  1. A magnetic key box: High-quality boxes like the ‘Hide-a-Key’ can be magnetically attached to the vehicle chassis. Ensure it is placed on a flat steel surface that does not get hot (avoid the exhaust).
  2. With a trusted contact: Give a copy to a partner or family member who lives within a 20-minute drive.
  3. At your office: Keep a spare in a locked drawer at work. This covers you if you lose your keys during the commute.

Do not keep the spare in the glove box. Insurance companies may deny your claim if the car is stolen using a key that was left inside the vehicle.

What About Digital Backups?

Technology offers some safety nets, but they have limits.

We see more drivers relying on these tools:

  • Manufacturer Apps: Apps like FordPass or Toyota Connected Services allow you to unlock the car via phone. This gets you inside, but usually won’t let you start the engine without the physical fob.
  • Key Codes: In your owner’s manual or service logbook, look for a card with a “Key Code” (usually a series of letters and numbers). Photo this card. It saves us time decoding the lock, which can lower your labour cost.

The Return on Investment

Let’s treat this like a financial investment.

  • Initial Cost: A spare smart key costs roughly $300.
  • Potential Savings: It prevents $300 to $800 in emergency fees, towing, and surcharges.
  • Duration: The asset lasts for the lifetime of the vehicle.

That is an immediate return of up to 160% on your money if you ever lose your key.

Calculator showing the return on investment of getting a spare car key compared to emergency replacement costs

The Bottom Line

The maths is undeniable.

Getting a spare car key is 40% to 60% cheaper than an emergency replacement. It eliminates the risk of expensive towing fees and protects you from being stranded in vulnerable situations.

If you are driving with only one key, contact a professional automotive locksmith this week. Your future self will appreciate the foresight. For a detailed breakdown of what to expect, check our car key replacement cost guide for Sydney.

spare car keykey replacement costcar key backuplocksmith advicesave money

Need a Locksmith Right Now?

Call us 24/7 for emergency lockouts, car key replacement, and ignition repair. We'll be there in 20 minutes or less.