

Change or rekey · Wilmot
Mailbox Lock Replacement
The mailbox key snapped clean off in the lock last week, and the stub is still sitting somewhere inside the cylinder.
In plain words
Small outdoor cam locks take a beating over a Canadian winter: road spray, salt, and repeated freezing leave the keyway gritty and the cylinder stiff long before the metal actually fails. Replacement at that point is straightforward, since the lock is a self-contained unit that unscrews from inside the compartment door. The new cylinder goes in following its own maker's lubrication instructions from day one, and a couple of fresh keys mean the whole assembly turns smoothly again.
How the visit goesThe mail slot on the shop's exterior wall has a small compartment lock that a former employee still has a key to, months after they left. Nobody on staff can say with any confidence who else might hold a copy.
Mailbox Lock Replacement
How the visit goes


How the old lock is held in
Most small mailbox locks are held in place from the inside of the compartment door by a nut, a spring clip, or a pair of small screws, rather than by anything visible from the front. Reaching that fastener means opening the compartment first, which is straightforward if a working key is still available and slower if it is not. Years of moisture and road salt can seize the fastener itself, and the locksmith checks for that early, since a corroded retaining nut changes how the old lock has to come out.
Working through a full panel
When a property manager has asked for several compartments changed together, each one is still confirmed against the unit number or resident it belongs to before its lock comes out, and the work moves door by door rather than as one blanket swap. Compartments stay keyed separately from each other unless a resident specifically asks for their mailbox and another lock to share a key. A panel-wide visit closes with a simple list: which compartment received which lock, and how many keys went to each person.
A record for the building
On a job arranged through a property manager or superintendent, the visit closes with a short account of what was done: which compartments were changed, how many keys went to each resident, and whether any doors were keyed alike on request. That note is handed to whoever coordinated the work, giving the building an accurate record instead of a guess about which locks are new and which are original to the panel.
Mailbox Lock Replacement
In the van
Straight and offset cams
Penetrating lubricant
Retaining nut or clip
Nut driver and screwdrivers
Cam lock cylinder

Mailbox Lock Replacement
What affects the quote
Condition of the compartment door
A door that has been bent, pried at, or knocked out of alignment on its hinge needs straightening alongside the lock, which is separate work from the lock swap itself.
Number of keys cut
Two keys is the usual starting point. Extra copies for other household members, or for several residents on a shared panel job, are counted individually into the visit.
Cam length and orientation
An uncommon cam length, angle, or throw can mean sourcing a less standard replacement or adapting an available one, rather than reaching for the most common size on the shelf.
What to have ready
- Has a property manager or superintendent been told about this request?
- Is the current key lost, snapped, broken, or simply worn out?
- Is the mailbox a standalone box, a door slot, or a shared panel?
Mailbox Lock Replacement: questions
QuestionsI just moved in and have no key at all. Can you still help?
Yes, and it is a common reason for this visit. Ownership or a lease showing the address, plus photo identification, is generally enough to confirm the compartment is yours to change. The old lock is opened without a key using the same techniques used elsewhere, then swapped for a new one, so whoever held the previous key no longer has any use for it.
Can the same key operate my mailbox and my front door?
It can, if both locks share a compatible keyway and are fitted with cylinders cut to the same combination during the same visit. This is arranged upfront, since it means keying the mailbox lock to match an existing door rather than the usual standalone replacement. Each lock involved is tested afterward so a single key turns every door named, and any other locks on the property keep their own separate keys.
What causes a mailbox lock to wear out or start spinning?
Thousands of turns over the years wear down the small parts inside a cam lock the same way any cylinder wears, and a worn key accelerates it further. A cylinder that spins without engaging the cam usually means the connection between the two has failed, often from corrosion or metal fatigue rather than anything the resident did. Once that connection goes, replacement is simpler than trying to repair the worn parts individually.
Related services

- Deadbolt InstallationYou bought a keypad deadbolt online and pulled the old one off, only to find the hole in the door is a different size and the bolt latch sits at a backset the new kit does not list.
- Lock Replacement & UpgradeThree teenagers, a dog walker, a cleaner and one house key that keeps going missing.
- Vintage Mortise Lock ServiceSomeone painted the door years ago without removing the hardware.