What to Do Right Now If You've Lost Your Keys
First, check your home is secure. If you're locked out and worried someone might use your keys, call a locksmith immediately—don't wait. A mobile locksmith can arrive within the hour, let you in, and rekey your locks on the spot.
If you're inside and just realized your keys are gone, assess the risk. Did you lose them at a known location with no identifying info? Lower risk. Lost them with your address on a keychain or ID nearby? Higher risk—rekey today.
Avoid the temptation to hide a spare under a mat or planter. If someone has your keys, they'll check obvious spots. A trusted neighbor or a lockbox with a code you can change is smarter.
Rekey vs. Replace: What's the Difference?
Rekeying means a locksmith disassembles your existing lock cylinder, removes the old pins, and installs new ones that match a brand-new key. Your hardware—deadbolt, knob, finish—stays exactly the same. The old keys stop working instantly.
Most pin-tumbler deadbolts and knob sets can be rekeyed in minutes. Wafer locks (common on older doors) work the same way. The process is fast, affordable, and leaves no trace—your door looks identical.
Replacing means removing the entire lock and installing new hardware. You'd only do this if your locks are damaged, outdated, or you want to upgrade to a higher security grade (ANSI/BHMA Grade 1 or 2 deadbolts, for example).
For lost keys alone, rekeying is almost always the right call. You save money, save time, and your door hardware matches the rest of your home.
When Rekeying Is the Best Choice
Rekey if your locks are in good shape and you simply need new keys. This covers most lost-key situations. A locksmith can rekey all your exterior doors to work on a single new key—front, back, garage entry—so you're not juggling a ring full of duplicates.
Rekeying also makes sense after a breakup, roommate move-out, or if you've handed out keys to contractors or housesitters over the years. You don't need to know who still has a copy; rekeying invalidates every old key at once.
If you're renting, check your lease first. Many landlords require you to call them before changing locks. Rekeying usually satisfies that rule because you're not altering the hardware—just the key profile.
When You Should Replace Instead
Replace your locks if they're already worn, sticking, or using outdated mechanisms. Builders often install Grade 3 deadbolts (the lowest ANSI rating) to save money. If your lock feels flimsy or the bolt doesn't extend a full inch, upgrading to a Grade 2 or Grade 1 deadbolt adds real security.
Consider replacement if you want smart locks or keyless entry. Most smart deadbolts require a specific backset (the distance from the door edge to the center of the bore hole—usually 2⅜″ or 2¾″) and bore diameter. A locksmith can confirm fitment and install in one visit.
Also replace if your door has been kicked in or the strike plate is damaged. Reinforce the frame with a heavy-duty strike plate (3″ screws into the stud, not just the trim) and a solid deadbolt. Rekeying won't fix structural damage.
How Much Does Rekeying Cost?
Expect to pay $20–$30 per lock for rekeying at a shop, or $50–$75 per lock for mobile service (where the locksmith comes to you). That's far less than replacing a quality deadbolt, which runs $100–$250 per lock including labor and hardware.
Some locksmiths charge a trip fee on top of per-lock pricing. Half Off Locksmith quotes a flat rate up front before dispatch—no hidden fees, no surprises. You'll know the total before we leave the shop.
If you're rekeying multiple locks at once, ask about volume discounts. Rekeying four or five exterior doors in one visit is faster and cheaper per lock than spacing them out.
Can You Rekey Locks Yourself?
Technically, yes—rekey kits exist for common brands like Kwikset and Schlage. You'll need the kit that matches your lock brand, a plug follower, tweezers, and patience. Most homeowners find it fiddly and time-consuming, especially if you've never disassembled a lock cylinder.
If you drop a pin or spring, or reassemble the plug out of alignment, the lock won't work. You'll need a locksmith anyway, and now you've added reassembly labor to the bill.
A mobile locksmith rekeys a lock in five to ten minutes per cylinder, often while you watch. The cost difference is small, and you skip the learning curve and the risk of a non-functional lock overnight.
Other Security Steps After Losing Keys
Rekeying stops the old keys from working, but take a broader look. If your keys were on a ring with a garage door opener or car fob, reprogram or replace those too. Most garage openers let you reset the code or rolling code sequence in the unit's settings.
Check window locks and sliding door security bars. If someone is bold enough to try a key, they might also check for unlocked side access. A simple dowel in a sliding door track or a keyed sash lock on a ground-floor window adds a layer.
If your keys were lost with mail, a wallet, or anything showing your address, consider a police report. It creates a record if something does happen, and some insurers want documentation for claims.
For more on residential locksmith services or to explore other security upgrades, visit our blog for guides on deadbolt grades, smart locks, and emergency lockout procedures.