To get a mailbox key from the Post Office, you visit the retail counter in person with two forms of valid U.S. ID and either open a new PO Box (PS Form 1093), request a key for a USPS-owned cluster box at your new address, or file PS Form 1094 to replace a lost key. Fees run from a $5.50 refundable deposit per key to $27 for a full lock change when every key is gone. The route you take depends on which kind of mailbox you have.
First, Figure Out Who Actually Owns the Mailbox
One detail decides everything else: is the mailbox managed by the USPS, or by a private party?
A PO Box is the locked compartment inside a Post Office building. The USPS owns it, controls the lock, and issues the keys directly to you.1USPS. PO Boxes For any key question, the Post Office is your only stop.
A cluster mailbox (also called a CBU) is the freestanding multi-unit box outside subdivisions, condos, and apartment complexes. Ownership varies. Sometimes the builder or property manager owns the unit and handles keys; other times the USPS does.2USPS. Locked Mailboxes and Mailbox Keys If you don’t know which, ask your property manager or the local Post Office before making a trip.
What to Bring to the Counter
Every key transaction at the Post Office requires two forms of valid U.S. identification: one with a photo, one without. Both must be current and traceable to you.3USPS. PO Box Help
Acceptable photo IDs include a valid driver’s license, state ID card, passport, or military ID. Your second document needs to confirm your address — a current lease, mortgage, deed of trust, voter or vehicle registration, or a home or vehicle insurance policy all qualify.4USPS. Acceptable Forms of Identification
Social Security cards, credit cards, birth certificates, and digital IDs on your phone are not accepted.4USPS. Acceptable Forms of Identification
Opening a New PO Box
You can start the application online or do the whole thing at the counter. Either way, keys are handed to you in person after the associate verifies your ID and processes payment.1USPS. PO Boxes
To apply online, sign into your USPS.com account, search by ZIP code, pick a box size and location, and choose a payment period. The system generates PS Form 1093, which you print and bring to the Post Office with your two IDs.1USPS. PO Boxes
To apply in person, walk into the Post Office, ask the associate for PS Form 1093, and complete it there. You can also download the form ahead of time from usps.com.
Once payment clears, you’ll receive two keys. Extra keys beyond that initial pair cost more.1USPS. PO Boxes
Moving In and Needing a Cluster Box Key
If you’ve just moved into a home or apartment and the previous occupant didn’t leave a key, your next call depends on ownership.
For a USPS-maintained cluster box, contact your local Post Office. The Postal Service changes the lock before assigning a compartment to a new resident, and there is no charge to you for that first lock change and set of keys.2USPS. Locked Mailboxes and Mailbox Keys Bring your two forms of ID and proof you live at the address.
For a privately owned cluster box, contact your landlord, property manager, or HOA. They handle keys and lock changes for those units. Fees and timelines are theirs to set. The USPS delivers to the box but plays no role in key management.2USPS. Locked Mailboxes and Mailbox Keys
Replacing a Lost or Damaged Key
Replacement depends on two things: whether you still have at least one working key, and whether the box is USPS-owned.
PO Box Replacement
Go to the Post Office where your box is located. Complete PS Form 1094 (“Request for Post Office Box Key or Lock Service”) and show your ID. If you still have one key, the counter can cut a duplicate for $13.00.5USPS. Notice 123 – Price List
If every key is gone, it’s a bigger job. The USPS keeps no duplicates, so the lock itself has to be replaced and a new set of keys issued at your expense.2USPS. Locked Mailboxes and Mailbox Keys Lock replacement costs $27.00 as of 2026.5USPS. Notice 123 – Price List
Cluster Box Replacement
For a USPS-owned cluster box, contact your local Post Office. There is no set national fee. The USPS FAQ says the charge is “based on local costs.”2USPS. Locked Mailboxes and Mailbox Keys Bring ID and proof of address. Turnaround runs from a few days to several weeks, depending on the office’s workload and parts availability.
For a privately managed cluster box, the property manager or HOA handles it. Fees and timing are up to them.
Current 2026 Fees
USPS fees effective January 2026:5USPS. Notice 123 – Price List
- Refundable key deposit: $5.50 per key, returned when you turn the key back in.
- Duplicate or replacement key (after the initial two): $13.00 per key.
- Lock replacement when all keys are lost: $27.00.
- PO Box rental: $30 to $553 per six months, depending on box size and Post Office location.
Cluster box fees for USPS-maintained units have no fixed national price; the local office sets the amount.2USPS. Locked Mailboxes and Mailbox Keys Privately managed cluster boxes follow whatever the property owner charges.
Protecting Your Mail While You Wait
A lost key means mail sitting in a box you can’t open, or a key in someone else’s hands.
If you think the key was stolen, report it to the U.S. Postal Inspection Service at 1-877-876-2455 or online at uspis.gov.6United States Postal Inspection Service. Report A stolen mailbox key gives a thief direct access to checks, card offers, and other sensitive documents. Alert your bank and any company that mails you financial records so they can watch for fraud.
For a PO Box, ask the retail associate to hold your mail behind the counter until the new lock is installed. For a cluster box at home, request a free USPS Hold Mail service to pause delivery for up to 30 days. You can submit the request online at usps.com, by phone, or at the counter.7USPS. Hold Mail – Pause Mail Delivery Online The cutoff is 3 AM ET on the start date you want, and the minimum hold is three days.
Keep Paying During a Long Wait
If a lock change or key order is dragging on, keep your PO Box rental current. The USPS gives a 10-day grace period after the due date. If no payment arrives by then, the box closes automatically.8United States Postal Service. Policies, Procedures, and Forms Updates Losing access to the key does not pause your bill. If you’re on auto-renewal, make sure the card on file hasn’t expired.
Private Mailboxes at The UPS Store and Similar Shops
A mailbox rented at a commercial mail receiving agency (CMRA) such as The UPS Store is not a Post Office box, and the USPS does not handle its keys. You deal with the store directly. Opening one requires two forms of ID (one photo) and a completed PS Form 1583, which authorizes the CMRA to receive USPS mail for you.9USPS. Commercial Mail Receiving Agency (CMRA) Pricing, key deposits, and lock changes are all set by the business, so ask the store for its rate sheet.