Apply for a PO Box

PO Box sizes and monthly or annual rates vary by post office — pricing depends on box size and how competitive demand is at that specific location, so there's no single nationwide price. Larger, busier post offices often have waiting lists for popular sizes.

USPS uses five standard box size tiers, from Extra Small (a handful of letters) up to Extra Large (bulk business mail). The table below shows typical interior dimensions for each tier — actual availability and monthly pricing are set locally, so confirm both with the specific post office before applying.

Beyond convenience, a PO Box adds privacy and security: your mail stays locked inside the post office rather than sitting in a curbside box, and only you or people you authorize can open it. Most locations also allow 24/7 access to the box itself, separate from the retail counter's hours, so you can check your mail on your own schedule.

You rent a PO Box in 3-, 6-, or 12-month terms. A 3-month term requires automatic renewal with no opt-out; 6- and 12-month terms let you opt out of auto-renewal. Payment is due by the 10th of the month it's owed, and USPS closes the box on the 11th if payment hasn't posted — worth knowing if you're not set up on autopay.

To apply, you'll need two forms of ID: one with a photo (driver's license, passport, military ID) and one showing your current address if it's not on the photo ID (a utility bill or lease works). You can apply in person at the post office where you want the box, or reserve it online at usps.com and bring the printed application and your ID to that post office within 30 days to finish verification and get your keys or combination — USPS requires in-person ID verification for every PO Box, there's no fully online option.

Not every post office offers PO Boxes, and availability changes as boxes open up or waiting lists clear. If the size you want isn't available, you can choose a different size, try another nearby post office, or join the waiting list — USPS will contact you when a box opens up, and you'll have two days to claim it before it moves to the next person in line. Check the location listings on this site for the post office nearest you, then contact that location directly to ask about current box availability and pricing before making the trip.