Reviewed and expanded August 2026. Carrier rules, product availability, and pricing can change; confirm current details before shipping.
What is available
The USPS Postal Store currently shows free Priority Mail and Priority Mail Express boxes, envelopes, labels, and forms in a range of sizes. Availability and pack quantities can change, so use the Postal Store rather than an old third-party list.
Service-specific packaging matters
Before ordering a large quantity, confirm that the exact packaging is appropriate for the USPS service you intend to buy. Flat Rate packaging, for example, is different from ordinary neutral corrugated packaging.
When free USPS packaging is useful
- Your order fits the available package closely.
- You regularly use the corresponding USPS service.
- You value standardized sizes and easy replenishment.
When to buy plain boxes instead
A plain carton can be better when the product needs a size not offered by USPS, when you compare several services, or when an oversized free box creates unnecessary empty space.
Official source
USPS Postal Store — free Priority Mail supplies
For strategy beyond one carrier, see Free Shipping Supplies for Small Business.