Rekey if the lock hardware is solid and you just want to change who has access. Replace if the lock is worn, damaged, or you want a security upgrade. Rekeying costs $125 + $45/lock. Replacement costs $75-$250/lock. Most new homeowners should rekey. Most people with 15+ year old locks should replace.
What's the Difference Between Rekeying and Replacing?
Rekeying changes the internal pins so old keys stop working. Replacing swaps out the entire lock. Think of rekeying like changing the password on your computer. The computer stays the same, but the old password no longer works. Replacing is buying a new computer.
When we rekey, we pull the cylinder out of the lock body, swap the pin configuration to a new pattern, and cut fresh keys. The lock hardware (the part you see on the door) stays exactly the same. Takes 20-40 minutes per lock and costs $125 for the service call plus first lock, then $45 for each additional.
When we replace, we remove the entire lock unit and install a brand new one. New cylinder, new bolt, new trim. The door prep (the holes in your door) usually stays the same because most locks use standard sizing. Takes 30-60 minutes and costs $75-$250 per lock depending on the grade.
When Should You Rekey?
Rekey when you want to change access but the hardware works fine. The most common rekeying situation: you just bought a house. According to the National Association of Realtors, over 5.4 million existing homes sold in the US in 2025. Every single one should be rekeyed. The previous owner, their realtor, their pet sitter, their cleaning service, and who knows who else all have copies of your keys.
Other good reasons to rekey:
- You fired a contractor or service provider who had a key
- A roommate moved out
- You lost a key and can't account for it
- Tenant moved out of your rental property
- You want all locks keyed alike (one key opens everything)
In all these cases, the lock hardware is fine. You just need new pins and new keys. Rekeying is the right call.
When Should You Replace?
Replace when the physical hardware is compromised or outdated. If the deadbolt doesn't throw smoothly, the knob wobbles, the cylinder is scored from a break-in attempt, or the finish is corroded from salt air exposure, replacement makes more sense than rekeying a lock that's on its last legs.
Also replace if you want a security upgrade. Builder-grade locks (the Defiant or low-end Kwikset that came with your house) are ANSI Grade 3, the lowest rating. An ANSI Grade 1 deadbolt like the Schlage B60N costs $40-$60 more but lasts 5x longer and resists forced entry significantly better.
And obviously, replace if you want to switch to a smart lock or keypad lock. You can't convert a standard mechanical lock into a smart lock by rekeying.
How Much Does Each Option Cost?
| Option | Cost per Lock | Best For |
|---|---|---|
| Rekeying (first lock) | $125 (includes service call) | New homeowner, tenant turnover |
| Rekeying (additional) | $45 each | Multiple locks, same visit |
| Replace with Grade 2 | $75-$150 | Worn locks, basic upgrade |
| Replace with Grade 1 | $120-$250 | Security-conscious homeowner |
| Replace with smart lock | $150-$400 | Tech-savvy, keyless entry |
| Replace with high-security | $200-$450 | Maximum security, key control |
For a typical 4-lock house, rekeying runs about $260. Replacing all four with Grade 1 deadbolts and matching knobs runs $600-$900. The right choice depends on the condition of your current hardware and your security goals.
Can You Rekey Locks Yourself?
Technically, yes. Practically, probably not. Kwikset SmartKey locks have a DIY rekeying feature that works with a special tool. But you need the current working key, the SmartKey tool (about $10), and steady hands. If you mess up the pin alignment, the lock can jam permanently.
For every other brand (Schlage, Medeco, Yale, etc.), rekeying requires removing the cylinder, using a pinning kit, and cutting new keys on a key machine. That's not a DIY job. The tools alone cost more than hiring a locksmith.
Our Honest Recommendation
If your locks are under 10 years old and work fine, rekey. If they're over 15 years old or showing wear, replace. If they're builder-grade junk regardless of age, replace with something better. That's the straightforward advice we give every customer who asks.
When we arrive, we'll look at your locks and give you both options with honest pricing. We don't push replacement when rekeying will do. We don't rekey a lock that's about to fall apart just to save you $50 today when it'll cost you $150 to replace next month.