Short answer: A USPS PO Box costs from $31 to $677 for six months, depending on the box size and the Post Office’s fee group. The smallest box (Size 1) costs $31 to $170 for six months, about $5 to $28 a month. You can pay for 3, 6 or 12 months. These are the USPS prices effective October 4, 2026.
USPS PO Box Prices by Size (October 2026)
Every Post Office belongs to a fee group, and the fee group sets the price. The table shows the lowest and highest price for each size across all fee groups.
| Box size | Inside dimensions | What fits | 3 months | 6 months |
|---|---|---|---|---|
| XS (Size 1) | 3″ x 5.5″ | 10 to 15 letters, 3 rolled magazines | $21 to $98 | $31 to $170 |
| S (Size 2) | 5″ x 5.5″ | 15+ letters, 5 rolled magazines or 1 Small Flat Rate Box | $26 to $130 | $41 to $225 |
| M (Size 3) | 5.5″ x 11″ | Stacked large envelopes and 2 Small Flat Rate Boxes | $38 to $228 | $60 to $395 |
| L (Size 4) | 11″ x 11″ | Small and Medium Flat Rate Boxes plus 10 to 15 letters | $55 to $259 | $90 to $452 |
| XL (Size 5) | 12″ x 22.5″ | Several packages | $96 to $389 | $156 to $677 |
Source: USPS Notice 123 price list, effective October 4, 2026, and the USPS PO Box size guide. Most boxes are 14.75 inches deep, and not every size is available at every Post Office.
Why PO Box Prices Vary by Location
USPS sorts Post Offices into two price systems:
- Market dominant locations use fee groups 1 to 7. Group 7 is the cheapest, with a Size 1 box at $31 for six months.
- Competitive locations use fee groups C30 to C44. Group C30 is the most expensive, with a Size 1 box at $170 and a Size 5 box at $677 for six months.
- Fee group E boxes are free. They go to customers whose address is not eligible for carrier delivery.
To see the exact price at a specific Post Office, enter your ZIP Code in the USPS PO Box search and select the location and box size.
Other PO Box Fees
| Fee | Cost |
|---|---|
| Key deposit, per key | $6 (no deposit for the first two keys at competitive locations) |
| Extra or replacement key, after the first two | $14 each |
| Lock replacement or late payment | $30 |
Payment is due by the 10th of the month it is owed. USPS closes the box on the 11th if you have not paid. A 3-month term requires automatic renewal. The 6- and 12-month terms let you opt out of automatic renewal.
How to Rent a PO Box
- Find a box at a Post Office near you on USPS.com and choose the size and payment period.
- Apply online and pay, or fill out PS Form 1093 and apply at the counter.
- Bring 2 forms of acceptable ID to the Post Office where the box is, within 30 days of applying online.
- Pick up your keys or lock combination after the clerk verifies your identity.
For the full process, see how to set up a PO Box. You can rent a box in another city or state, but you still pick up the keys in person. Read can I get a PO Box in another state.
What a PO Box Cannot Do
- Receive packages from UPS, FedEx, DHL or Amazon unless the Post Office offers Street Addressing and you add it.
- Serve as your LLC’s registered agent address. Every state requires a physical street address for the registered agent.
- Serve as a principal office address in most states, which require a street address.
- Show you your mail remotely. You go to the Post Office to collect it, and packages that do not fit wait at the counter or in a parcel locker.
See can you use a PO Box for an LLC.
PO Box vs. Virtual Mailbox: Cost and Features
| USPS PO Box | Virtual mailbox | |
|---|---|---|
| Monthly cost | About $5 to $113, by size and location | From $20 a month billed annually at BusinessAnywhere |
| Address type | PO Box number (street format with Street Addressing, where offered) | Real street address with a suite number |
| Packages from private carriers | Only with Street Addressing | Yes, from every carrier |
| See your mail from anywhere | No | Yes, every envelope scanned online |
| Forwarding | Change of address only | On request, to any country |
| Works as an LLC principal office | No in most states | Yes |
| Pickup | In person at the Post Office | Not needed |
If you travel, live abroad or run a business remotely, a virtual mailbox costs less than a mid-size PO Box in most fee groups and works from anywhere. Compare more options in our guide to PO Box alternatives.
FAQs
How much is a PO Box per month?
A Size 1 PO Box costs about $5 to $28 a month, based on the six-month price of $31 to $170. The largest box costs about $26 to $113 a month. USPS bills for 3, 6 or 12 months at a time, not monthly.
What is the cheapest PO Box?
A Size 1 box at a fee group 7 Post Office costs $31 for six months or $21 for three months. Fee group E boxes are free for customers who cannot get carrier delivery at their address.
How much does a large PO Box cost?
A Size 4 box costs $90 to $452 for six months and a Size 5 box costs $156 to $677 for six months, depending on the Post Office.
What do I need to get a PO Box?
A completed PS Form 1093 (generated for you when you apply online), payment for the first term and 2 forms of acceptable ID shown in person at the Post Office.
Can a PO Box receive UPS and FedEx packages?
Only if the Post Office offers Street Addressing and you add it. You then use the Post Office’s street address with your box number, and private carriers deliver there.
Can I use a PO Box for my LLC?
You can use a PO Box as a mailing address. It cannot be your registered agent address, and most states reject it as a principal office address. A virtual mailbox gives you a street address that works for both mail and your principal office.
