Is It Cheaper to Rekey or Replace Your Locks?

Rekey or Replace? How to Decide What Your Locks Need

You have moved into a new home, lost your keys, or split up with someone who has a copy. You want to make sure old keys no longer work. The question is: should you rekey the existing locks or replace them entirely?

I am Ross, a local locksmith based in Coventry. I handle these calls every week, and the honest answer is that for most residential properties in the Coventry and Warwickshire area, I recommend replacement over rekeying. Let me explain why — and when rekeying does make sense.

What Is Rekeying?

Rekeying means changing the internal pins or wafers inside a lock cylinder so that the old keys no longer work and a new set of keys is cut to match the new pin configuration. The lock body itself stays in place — only the internal components change.

Think of it this way: the lock is a puzzle, and the key is the solution. Rekeying changes the puzzle without replacing the whole lock. Your old keys become useless, and you get new ones that work with the reconfigured lock.

How Rekeying Works (Step by Step)

The lock housing, the mounting, and the external appearance all stay the same. From the outside, you would never know the lock had been rekeyed.

What Is Lock Replacement?

Lock replacement means removing the entire lock — housing, cylinder, everything — and fitting a brand new one. You get a completely new lock with new keys, and the old lock is disposed of.

Cost Comparison: Rekey vs Replace

Here is what each option typically costs for the most common lock types:

Euro Cylinder (uPVC and Composite Doors)

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Look at those numbers. For a euro cylinder, the cost difference between rekeying and replacing is minimal — sometimes replacement is actually the same price or cheaper. And with replacement, you get a brand new lock with full lifespan ahead of it.

Yale Nightlatch (Wooden Front Doors)

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Again, the price gap is small. A new Yale nightlatch costs only £10-£25 more than rekeying the old one.

5-Lever Mortice Deadlock (Wooden Front Doors)

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Mortice locks are more complex to rekey than cylinder locks, which brings the rekeying cost up closer to the replacement cost.

When Rekeying Makes Sense

There are specific situations where rekeying is genuinely the better option:

1. High-Quality Locks That Are in Good Condition

If you have expensive, high-quality locks that are relatively new and in perfect working order — for example, an Ultion cylinder that is only a year old — rekeying saves you from replacing something that does not need replacing. You keep the premium lock and just change the key configuration.

2. Decorative or Custom Hardware

Some locks are part of decorative door hardware that would be difficult or expensive to replace. Antique locks on period properties, custom-finished handles with integrated locks, or commercial-grade hardware where the lock body is built into a bespoke system — in these cases, rekeying preserves the hardware while changing the keys.

3. Commercial Properties With Master Key Systems

In offices and commercial buildings, locks are often part of a master key system where different keys open different doors but a master key opens all of them. Rekeying lets you change individual locks within the system without disrupting the entire hierarchy. This is not common in residential properties, but it is worth mentioning.

4. Multiple Locks Keyed Alike

If you want all your locks to work with the same key (keyed alike), rekeying existing locks to match one key can sometimes be more cost-effective than replacing all of them — especially if the locks are good quality and varied in type.

When Replacement Is Better

For most standard residential locks in Coventry, I recommend replacement. Here is why:

1. The Anti-Snap Upgrade Opportunity

If your uPVC or composite door has a standard euro cylinder (not anti-snap), replacing it gives you a security upgrade at virtually no extra cost compared to rekeying. Lock snapping is the [most common burglary method](/blog/what-is-lock-snapping) for uPVC doors in the UK. Replacing a standard cylinder with an anti-snap one is one of the best security investments you can make — and it costs the same as rekeying would.

Why would you pay £40-£60 to rekey a vulnerable standard cylinder when you can pay £59 for a brand new anti-snap one?

2. Worn or Aging Locks

Locks wear out. Pins get rounded, springs weaken, and the mechanism becomes stiffer over time. Rekeying a worn lock gives you new keys but the same worn internals. Within a year or two, you will probably need to replace it anyway.

If your key has been getting stiffer over the last few months, or if the lock is more than 10 years old, replacement makes more sense than rekeying.

3. Cheap or Low-Security Locks

Many UK homes — especially those with uPVC doors — have the cheapest euro cylinder the door manufacturer could find. These budget cylinders have poor pin quality, no anti-pick features, and no anti-snap protection.

Rekeying a cheap lock gives you new keys for a cheap lock. Replacing it gives you new keys for a good lock. The cost difference is minimal.

4. Peace of Mind

There is something psychologically reassuring about a completely new lock. When you move into a new home and want to know that nobody else has a working key, a new lock provides that certainty. Yes, a rekeyed lock achieves the same practical result — old keys will not work. But a new lock removes any doubt.

5. The Cost Difference Is Not Significant

For standard residential locks, the price difference between rekeying and replacing is typically £10-£25. That is a small amount to pay for a brand new lock with a full lifespan, potentially better security features, and complete peace of mind.

My Honest Recommendation

For the vast majority of residential lock jobs in Coventry, I recommend replacement over rekeying. Here is my reasoning:

The exception is if you have premium locks (Ultion, ABS, Avocet) that are in good condition and only a few years old. In that case, rekeying saves you from replacing expensive hardware unnecessarily.

Common Scenarios and My Recommendation

Moving House

Recommendation: Replace. You do not know the history of the existing locks, their age, or their quality. Start fresh with new locks. I do a lot of [moving house lock changes](/blog/moving-house-change-locks) across Coventry — it is one of the most popular jobs.

For a typical Coventry home with one uPVC front door and one uPVC back door, expect to pay from £100-£130 for both cylinders replaced with anti-snap upgrades. A wooden front door with a Yale and mortice deadlock runs from £130-£150 for both locks replaced.

Lost Keys

Recommendation: Replace (for standard locks) or Rekey (for premium locks in good condition). If you have lost your keys and there is a risk someone could use them, you need to act. Replacing standard cylinders is fast, affordable, and gives you a security upgrade. If you have premium locks, rekeying preserves your investment. Either way, read our guide on [what to do if you have lost your keys](/blog/lost-keys-should-you-change-locks).

Relationship Breakdown

Recommendation: Replace. When someone who should no longer have access has keys to your home, a complete lock change provides both security and peace of mind. This is a job where the psychological reassurance of new locks matters as much as the practical security.

Landlord — Between Tenants

Recommendation: Replace. As a landlord, you do not know how many key copies the previous tenant made or who they gave them to. A new cylinder for each external door is cheap insurance. See our guide on [landlord lock change obligations](/blog/landlords-change-locks-between-tenants).

After a Break-In

Recommendation: Replace and upgrade. After a burglary, you want the best locks you can get — not the same locks with different keys. This is the time to upgrade to [anti-snap cylinders](/services/lock-upgrade), add a deadlock if you do not have one, and review your overall security. Our guide on [what to do after a burglary](/blog/what-to-do-after-burglary) covers the full process.

Getting the Right Advice

If you are not sure whether to rekey or replace, call me on 07735 336175. I will ask about your locks, your situation, and what you are trying to achieve — and give you an honest recommendation. No pressure, no upselling.

I cover the whole Coventry and Warwickshire area, same price 24/7. Check our [lock change service page](/services/lock-change) for more details, or see the full [price list](/prices) for every job we do.