Mailbox Lock Replacement Starts With Who Owns the Box

2026-10-24

First Find Out Who Owns Your Mailbox

You're standing at the mailbox with a key that won't turn. Or no key at all. You want a new lock today.

Who owns the box sets everything else. It decides who may touch the lock. It decides who pays. And it decides if a locksmith can help at all.

Most people guess wrong. A metal bank of boxes on a pole looks the same whether the Post Office owns it or your HOA does. The rules are not the same.

Not sure which one you have? Ask your carrier or the counter at your Post Office. They know which boxes on the route are theirs. If you rent, start with the leasing office.

Cluster Boxes the Post Office Owns

The Post Office writes its own rules for these boxes. They're in the Postal Operations Manual, section 632. Section 632.22 is short and clear.

• You get a compartment lock and three keys. No key deposit.
• You may copy your keys. The Post Office doesn't pay for the copies.
• The Post Office keeps no spare keys.
• Lose all three, and the Post Office puts in a new lock at your expense.
• When someone moves out, the Post Office should change the lock. The new person doesn't pay for that first lock and keys.

So you can't get a spare from the counter. And you can't hire a locksmith to swap the lock. The lock belongs to the Post Office.

What You'll Pay

The Post Office prices PO Box locks in Notice 123. As of October 2026, a PO Box lock replacement is $30. A key after the first two is $14 each. A key deposit is $6 per key.

Notice 123 has no separate line for a cluster box lock. The manual only says to charge the customer for the repair. So ask the counter what your office charges before you go.

What to Bring

Bring a photo ID and proof you live at the address. A lease, a deed or a utility bill works at most counters. The form for PO Box key or lock service is PS Form 1094, per the USPS forms list. Ask if your office uses it for cluster boxes too.

Hands Off the Lock

Don't drill it. Don't pry it. Federal law, 18 U.S.C. 1705, makes it a crime to break open a mailbox used for mail delivery. The max is three years in prison. 18 U.S.C. 1704 covers postal keys. Making one without the right to can mean up to ten years.

Copying your own three keys is fine. The manual says so. Cutting a key to a box that isn't yours is not.

Apartment, Condo and HOA Boxes

Here the building owns the boxes, not the Post Office. The manual's note under 632.22 says the builder or owner handles lock and key service on a cluster box they bought.

Lobby wall boxes work the same way. Section 632.625 tells managers to keep a record of each lock's key number. That's how they order you a new key without changing the lock. It also says master keys are not allowed on these boxes.

The manual puts repairs on the owner or manager too. It says repairs should be done with a postal worker present, so mail isn't exposed. That's one more reason not to change a tenant box yourself.

So your first call is the leasing office or the HOA. Ask three things.

1. Do you have my lock's key number on file?
2. Will you cut a new key, or change the lock?
3. What does it cost, and how soon?

Your lease or HOA rules set the price. Some offices send their own maintenance worker. Others send a locksmith. Moving in? Ask for the mailbox keys at the same time as the door keys. If the last tenant kept a set, ask for a new lock before you get mail there.

Our guide to moving into a new home covers the other locks to change that first week.

A Box You Own at Home or Work

This is the only box you can work on yourself. A locking curbside box, a wall box by your door, a parcel box at your office. It's your lock to change.

Not Every Curbside Box Can Lock

This catches people on rural routes. Section 632.527 of the manual says locks and locking inserts on curbside boxes are not allowed on rural and highway contract routes. The carrier won't open a locked box. The Post Office won't take a key.

The way around it is an approved locking mailbox. It has a slot, so mail drops in without a key. The Post Office lists approved makers in the Postal Bulletin. The May 2023 list names locking models from Architectural Mailboxes, Mail Boss, Mailcase, Salsbury, Postal Vault and others.

Buy the Lock From the Box Maker

Start with the brand of your box. The maker's own lock fits the hole and comes with the right cam. As of October 2026, Mailcase sells a replacement lock for $24.99 with six keys. Mail Boss lists its kit at $32 with three keys and the cam for your model. Mail Boss says to check the silver tag inside the upper door if you don't know your model.

No brand name on the box? Take the old lock with you to the store. Match the length of the cylinder and the shape of the cam.

The Swap

1. Open the door. Pry it gently or call a locksmith if the key is gone.
2. Take off the nut on the back of the lock. Lift off the cam.
3. Pull the clip, then push the old cylinder out the front.
4. Slide the new one in. Put the clip and a cam that matches the old one back on.
5. Snug the nut. Test the key with the door open, then closed.

Locked out of your own box with mail inside? A locksmith can open it and fit the new lock in one trip. That's often cheaper than wrecking the door.

What Locksmiths Get Called Out For

We list thousands of locksmiths, and we read what their customers say. As of October 2026, 34 reviews on the shops we list talk about a mailbox job. 16 were a lock swapped or rekeyed. 15 were keys copied or cut new. The rest were lockouts and security upgrades.

A few things showed up again and again.

• Store copies often fail. One landlord tried three big box key counters for a tenant's spare. Each key fit the slot and wouldn't turn. A locksmith got it right.
• Kiosks don't stock every blank. Mailbox keys are odd shapes. A shop with a full wall of blanks had the one a kiosk didn't.
• No key isn't the end. In Anchorage, a shop cut a working key from the code on the lock, using a photo.
• Prices swing. A Hemet customer paid $30 for a mailbox key after other quotes of $80 to $140. An Irvine shop told another customer there was a $75 minimum.
• Condo and HOA boxes get locksmith visits. Several reviews were condo owners or property managers who had a shop change the locks. The owner or manager made that call.

Copies are the cheap part. Two reviewers paid under $5 and under $10 for a spare at a local shop. A trip out to open and change a lock costs more. Ask for the full price on the phone, trip charge included. Our locksmith cost guide shows what a service call usually adds.

When you call, say what kind of box it is. A good shop will ask who owns it. If it's a Post Office box, they should send you to the counter. A shop that offers to drill one is a shop to skip. Our page on spotting a locksmith scam lists the other warning signs.

Where Other Guides Slip

Plenty of mailbox guides say you can't copy a Post Office cluster box key. The manual says the opposite. You may copy your keys. The Post Office just won't pay for them or keep a spare.

The fee numbers online are all over the place. One page quotes $20 to $30, then $30 to $35 a few lines later. The real list price is in Notice 123, and it covers PO Boxes. For a cluster box, the manual only says the customer pays for the repair. Call your office.

Almost nobody mentions the rural route rule. You can't just bolt a lock onto a regular curbside box out in the county. Buy a locking box with a slot from the approved list.

And some guides tell you to call a locksmith for any stuck mailbox lock. For a Post Office box, that's the wrong call. Go to the counter. For a box you own, a locksmith is a fine call. Our post on which keys can't be copied covers the federal key law in more depth.

★Star Locksmith Listing as a source in Google

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