You just moved in, lost a key, or had a contractor or ex-roommate leave with a copy. Now you want to know who else can open your door. Most people ask the same question: should I rekey the locks or replace them?
Both work, and each is the better choice in different situations. Here is how to decide, and what a locksmith checks before recommending one.
What’s the difference?
Rekeying changes the inside of the lock so it works with a new key. A locksmith swaps the small pins inside the cylinder to match the new key. The lock stays on your door, looks the same, and your old keys stop working.
Replacing means removing the old lock and installing new hardware, such as a new deadbolt, knob, lever, or smart lock. You get new keys with the new hardware.
The main point: rekeying changes who has access, but it doesn’t make a weak lock stronger. Replacing can change both.
When rekeying is the better choice
Rekey when the hardware is in good shape and you mainly want to cancel old keys:
- You just bought or moved into a home. You don’t know how many copies of the old keys exist.
- You lost a key. Rekeying makes the lost key useless.
- Someone who had a key no longer should. Think ex-partner, former roommate, previous tenant, contractor, or house cleaner.
- You want one key for every door. A locksmith can rekey the front door, back door, and other locks to match.
- The locks are in good condition and good quality. If they turn smoothly and look sound, there’s no reason to throw them out.
- You like the current look. Rekeying keeps your existing finish and style.
- You have an older mortise lock. Many can be rekeyed and are worth keeping. See our page on mortise locks, or our guide on how mortise lock repair can improve home security.
When replacing is the better choice
Replace when the problem is the lock itself:
- The lock is worn, loose, rusty, or damaged. If the key sticks, the latch drags, or the deadbolt doesn’t throw fully, new hardware is more reliable.
- It’s a low-grade lock. Locks are rated by grade under ANSI/BHMA standards. Residential locks generally fall into Grade 2 or Grade 3, and Grade 1 is the toughest. For an entry door, aim for at least Grade 2. Our locks and locksmiths page can help you choose. Read more about the standards in this Locksmith Ledger guide to ANSI/BHMA residential hardware.
- You’ve had a break-in or attempted break-in. Replace any damaged hardware and check that the door frame and strike plate are solid too.
- You want a security upgrade. That could be a stronger deadbolt, a better cylinder, or a keyless entry system. See our post on the benefits of upgrading home locks, or our Schlage smart deadbolt page.
- You want a new style or finish. New hardware can refresh your door’s curb appeal.
- The lock can’t be rekeyed. Some cheap or very old locks can’t be rekeyed, or the parts are no longer available.
- A key broke and damaged the cylinder. Repeated sticking, broken keys, or a gritty feel can mean the cylinder is worn out.
Quick comparison
| Situation | Rekey | Replace |
| New home, locks in good shape | ✅ | |
| Lost or stolen key | ✅ | |
| Former tenant, contractor, or roommate had keys | ✅ | |
| Want one key for all doors | ✅ | |
| Lock is worn, loose, or sticking | ✅ | |
| Low-grade builder hardware | ✅ | |
| Break-in damage | ✅ | |
| Want a smart lock or stronger security | ✅ | |
| Want a different look | ✅ |
What about smart locks?
With a smart lock you usually change the access codes instead of the keys. The backup key cylinder can still be rekeyed if you want to cancel old physical keys. If your door has a smart lock that is acting up in winter, see our post on why doors and locks stick in cold weather.
Is DIY rekeying a good idea?
DIY rekey kits exist for some brands. But a small mistake, like a wrong pin or a badly seated cylinder, can leave a lock that binds, sticks, or doesn’t lock properly. A locksmith also looks at the whole door while there. They check whether the deadbolt fully extends into the frame, whether the strike plate lines up, and whether the door sags. If the door has alignment problems, our door repair services can fix that in the same visit.
What a locksmith checks before recommending
- The brand and type of lock, and whether it can be rekeyed.
- The lock’s condition: wear, corrosion, loose parts, and how the key feels.
- The lock’s grade and overall quality.
- How the door, frame, and strike plate are working together.
- Your goals: cancel old keys, get one key for everything, or upgrade security.
Our guide on how locksmiths handle emergency lockouts is a useful read if you’ve lost your only key and can’t get in. For ongoing care, see why regular lock maintenance pays off.
For business owners
The same logic applies to offices and shops. Rekey after an employee leaves or a key goes missing. Replace worn-out or low-grade hardware. If you have many doors and many staff, ask about a master key system. Our commercial locksmith page covers business options.
FAQs
Does rekeying make my lock more secure?
It stops old keys from working, which improves who can get in. It doesn’t make a weak lock stronger. If the lock is low quality or damaged, replace it.
Should I rekey after moving into a new home?
Usually yes. You don’t know who has copies of the old keys, and rekeying is a simple way to start fresh.
Can every lock be rekeyed?
No. Most standard locks can, but some cheap, damaged, or very old ones can’t. A locksmith can tell you quickly.
Will my lock look different after rekeying?
No. The lock stays on the door, so the look doesn’t change.
Is rekeying faster than replacing?
Usually, yes. It doesn’t require new hardware, and the lock stays on the door.
Can all my doors use the same key?
Yes, in most cases. Ask your locksmith to rekey them so one key works for every lock.
Get it done by a local locksmith
Harvey’s Lock and Door Service Inc helps homeowners and businesses across Delaware County and nearby areas, including Springfield, Wayne, Villanova, Haverford, and Ridley Park. See our locksmith services, then contact us or call 610-622-1800 to book a rekey or a lock replacement.