A PO Box costs $31 to $677 for 6 months in 2026
USPS sets PO Box prices by box size (1 is the smallest, 5 the largest) and by the fee group of your Post Office. The smallest box costs $31 to $170 for 6 months. The largest costs $156 to $677. Busy city Post Offices are in the higher fee groups.
PO Box prices for 6 months, from USPS
| Size 1 (smallest) | $31 to $170 |
|---|---|
| Size 2 | $41 to $225 |
| Size 3 | $60 to $395 |
| Size 4 | $90 to $452 |
| Size 5 (largest) | $156 to $677 |
| Size 1, paying every 3 months | $21 to $98 a quarter |
| Key deposit | $6 per key |
| Extra key after the first two | $14 each |
| Lock replacement or late payment | $30 |
The low end of each range is the cheapest fee group. The high end is the most expensive group, found in the busiest locations. Find your Post Office's fee group at usps.com. Source: USPS Notice 123, Price List, effective July 12, 2026 (Postal Explorer).
What changes your price
- Box size. Size 1 fits letters. Size 5 fits parcels and costs several times more.
- Your Post Office. USPS puts each location in a fee group. The same size 1 box costs $31 in the cheapest group and $170 in the dearest.
- How long you pay for. Paying 6 months at a time costs less than two 3 month payments.
Ways to pay less
- Check a Post Office in the next town. It may be in a cheaper fee group.
- Pay for 6 months, not 3. A size 1 box in the top group is $170 for 6 months but $98 for 3 months.
- Pick the smallest box that fits your mail.
How we got these numbers
USPS sets PO Box prices by box size and by the fee group of each Post Office. Every price on this page comes from USPS Notice 123, the official price list the Postal Service publishes. The prices we use took effect on July 12, 2026. Where we show a total, we simply add up the separate USPS fees, so you can see what one item costs all in. We do not add our own guesses or use a calculator. PO Box prices change with the fee group of each Post Office, so we show the lowest and highest group for each box size. USPS changes its prices from time to time, so check the price at the counter if your visit is far from September 26, 2026, the day we last checked.
Common questions
How much is a PO Box in 2026?
$31 to $677 for 6 months, depending on size and location.
How much is the smallest PO Box?
$31 to $170 for 6 months.
Is there a key fee?
Yes. A $6 deposit per key, and $14 for each key after the first two.