Short answer: yeah, technically they can. Should they? Not really. I hear this question a lot, usually right after someone's handyman "fixed" a lock and it's never quite been right since.
The honest answer
Look, if it's a simple swap - same knob, same holes, same backset, door's in good shape - a handyman can probably handle it fine. Plenty of them do this all the time without a problem. But here's something a lot of people don't realize: in Maryland and Virginia, locksmithing is actually a licensed trade. A handyman isn't required to have the training, background check, or licensing a locksmith has to have. That doesn't mean every handyman will mess it up, but it means you're not getting the same guardrails. It's one of the reasons Rockville homeowners keep calling Mike's first - not because we're the cheapest call, but because we're the right one. Knowing which key opens which lock starts with knowing what's actually on your doors, and sometimes that clarity is all it takes.
The problem is, "simple" isn't always simple.
Where it goes wrong
A lock looks basic from the outside, but inside it's a precision-fit system - cylinder, plug (the piece that turns with the key), springs, pins, strike plate - and all of it has to line up just right with the door and frame. Here's how a well-meaning handyman ends up causing more harm than good:
Over-tightened screws, and the latch warps so it binds or won't retract right
Misaligned strike plate, so the door looks locked but really isn't
Forced a lock that doesn't quite fit, and damages the door in the process
Doesn't re-key or account for spare keys, so you don't actually know who has access anymore
Missed a compromised cylinder - like a tampered plug - because spotting that takes lock-specific know-how, not general handyman skills
Installed it wrong altogether - we've gotten calls from people locked out of their own house, and others locked in, because of a bad install
That cylinder one is the sneaky one. The lock can look totally fine and still be easy to defeat. That's usually what Mike finds when someone calls him in after a "quick fix" didn't hold - a tampered plug, a stiff turn hiding a real problem, a lock that closes but isn't actually securing anything. And this is exactly why the lock on your door is your first line of defense - not your alarm system, not your camera, not your smart doorbell. The lockout/lock-in stuff is the opposite - no mystery there, just someone standing at their own front door realizing something's very wrong. This is also one of the five things worth checking before the time change - here's the full list.
Why it matters more than it seems
A bad install doesn't usually announce itself. It just quietly doesn't work right - until the day it really doesn't, or you find out it was never protecting you the way you thought. That's not something you want to discover after the fact. And if you've ever wondered why a locksmith needs to see your door before quoting a price, this is exactly why - because what looks like a simple job on the outside is often something else entirely once someone who knows what they're looking at actually looks. For a full picture of what separates a licensed residential locksmith from a handyman, start here. An untrained technician sent by a scam center makes those mistakes on purpose - here’s how to spot one before they touch your door.
The rule of thumb
Simple swap, door and frame already in good shape? A decent handyman is probably fine. But if there's any tampering, anything weird with how the door closes, any rekeying, or it's not a clean drop-in - call a locksmith. And honestly, the same goes if your lock just isn't working right, whether it's sticking, grinding, or acting up in some way you can't quite explain. That's a call for a locksmith, not a handyman - a handyman isn't trained to actually diagnose and fix what's going on inside a lock, and guessing at it can turn a small issue into a real security problem. It's not about turf. It's just that with lock security, "close enough" really isn't.
Got a lock question you want answered here? Send it my way - you're probably not the only one wondering. And if you need a residential locksmith who will actually look at the door before telling you what it needs, that's what we're here for.
We're Here When You're Ready
If you're in the DMV area and thinking about upgrading your home or business security - cameras, locks, smart access, or all of the above - we're always happy to talk it through.
Mike's Locksmith proudly serves homeowners and small businesses across Maryland, Virginia, and DC.
Also published on The Locksmith's Wife - read it on Substack
