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Home > Guides > UPS/FedEx to PO boxes
No, UPS and FedEx will not deliver to a USPS PO box. The one real workaround is USPS street addressing: your post office's street address plus your box number, formatted like an apartment address, lets private carriers deliver a parcel that you pick up at the post office counter.
A PO box lives inside a post office, and only USPS employees have access to it. UPS and FedEx drivers do not enter postal facilities to deliver, and their address-validation systems reject PO box addresses outright, often at checkout. If you somehow get a UPS label addressed to a PO box, the parcel usually bounces back to you, or the carrier holds it and asks for a street address. Either way, it adds days.
This confuses people because USPS itself delivers to PO boxes just fine. The issue is not the box. It is that two private companies cannot legally or practically open USPS's locked boxes. The same restriction applies in reverse: USPS cannot drop a parcel into a private UPS mailbox at a UPS Store. Each carrier's endpoints belong to that carrier.
Most US post offices offer a free service called street addressing for PO box holders. Instead of "PO Box 123", you write the post office's street address followed by your box number, like this:
Name
Post Office Street Address #123
City, State ZIP
To a private carrier's system, that looks like an ordinary street address with a unit number, so the label validates and the driver delivers the parcel to the post office's receiving door. USPS staff then sort it to your box or hold it at the counter for pickup. You pick it up like any other oversized parcel.
Three things people get wrong about this. First, you must check whether your post office participates; most do, but not all, and the USPS website lists participating locations. Second, the box-number format matters: use "#123" or "UNIT 123" style, never write "PO Box" on the line, because some carrier systems scan for that phrase and reject the address. Third, oversized parcels go to the counter, not into your box, so expect a pickup slip rather than a package in the little metal door.
| Option | Who delivers | Where you collect it |
|---|---|---|
| Ship USPS (Priority, Express, Ground) to the PO box | USPS, directly | Your box, or the counter for large items |
| Ship UPS/FedEx using street addressing | UPS/FedEx to the post office door, then USPS staff | Your box, or the counter for large items |
| Ship UPS/FedEx straight to "PO Box 123" | Nobody; it will be refused or returned | Back at the sender |
| Rent a private mailbox (UPS Store, etc.) | All carriers, including USPS | The store counter |
Contact the sender first. They can sometimes update the address through UPS My Choice or FedEx Delivery Manager before the parcel reaches your area. If it is already out for delivery, it will likely be returned to the sender, and the fastest fix is a new shipment to the corrected address. Ask the sender to reship with street addressing or with USPS service. This is also why online sellers get nervous about PO box addresses in their checkout systems: the store cannot tell which carrier will carry the parcel.
Canada works differently because Canada Post is both the PO box operator and the main parcel carrier. Canada Post delivers to its own PO boxes without any workaround, and a Canada Post shipping label addressed to a PO box works normally. Private couriers in Canada (Purolator, FedEx Canada, UPS Canada) generally need a street address, same as in the US. LetterAgent's shipping labels are Canada Post Xpresspost labels, so they reach PO boxes and rural addresses that private couriers sometimes cannot.
Ready to ship it? Get a shipping label with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and get your label.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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