The cheapest small shipping boxes are free USPS Priority Mail boxes, if you ship by Priority Mail; otherwise buy plain corrugated boxes in bulk online.
Free carrier boxes have one catch: each may only be used for the service printed on it. For USPS Ground Advantage you need your own box, and for any carrier the price per box falls as the pack size grows. Below: where to buy, which carrier boxes are free, and how to pick a size that keeps postage low.
Where can you buy small shipping boxes cheaply?
Packaging suppliers and large retailers sell plain corrugated boxes in packs, and buying 25, 50 or 100 at a time is the simplest way to cut the price per box.
Prices change daily, so compare the unit price (pack price divided by the number of boxes) for the exact size you need before you order.
| Store | Best for |
|---|---|
| Amazon | A very wide choice of box sizes and multipacks from many sellers, with reviews to compare quality |
| Uline | Wholesale packs in many sizes; Uline's box pages say orders placed by 6 PM ship the same day |
| Walmart | Small multipacks of corrugated boxes and poly mailers, in store or online |
| eBay Shipping Supplies | eBay's own store sells eBay-branded boxes, padded mailers, poly mailers and tape for sellers |
| Packagingsupplies.com and The Boxery | Packaging specialists with bulk packs and many stock sizes |
| Staples | Boxes, bubble wrap and packing supplies near you when you need a few boxes today |
| Lowe's | Single boxes and recycled cardboard boxes in home improvement stores |
| U-Haul | Heavy-duty moving boxes for heavier or tougher products |
Are USPS boxes free?
Yes: USPS gives away Priority Mail and Priority Mail Express boxes and envelopes, including Flat Rate boxes, but only for shipping with those services.
- What is free: USPS offers over 65 standard packaging supplies for Priority Mail Express, Priority Mail, Priority Mail Express International and Priority Mail International, at no charge when used as intended. The Postal Store lists the Priority Mail Flat Rate Small, Medium and Large Boxes at $0.00.
- How to get them: order on The Postal Store (usps.com/shop, then "Free Shipping Supplies"), add them to a label in Click-N-Ship, or call the Package Supply Center at 1-800-610-8734. Single quantities are free at most Post Office locations.
- Delivery: free supply orders ship within one business day by USPS Ground Advantage, with expected delivery in 2 to 5 business days at no cost. Priority Mail delivery of supplies (1 to 3 business days) costs a fee.
- The rule: USPS packaging must be used only for the product printed on it. Anything mailed in Priority Mail or Priority Mail Express packaging is charged that service's price, even if the box is turned inside out or the markings are covered, and misuse may violate federal law.
- What is not free: USPS Ground Advantage has no free boxes; USPS says to use your own packaging and measure it. Priority Mail Forever Prepaid Flat Rate packaging is also not free: it is sold online with the postage included, at the retail Flat Rate price.
Only USPS-produced Flat Rate boxes get Flat Rate prices, which cover up to 70 lbs to any domestic address. Sizes, prices and when Flat Rate pays off are in USPS Flat Rate Priority Mail explained.
Do UPS, FedEx and DHL give free boxes?
Yes, to account holders, and mostly for their express services rather than ground shipping.
- FedEx: with a FedEx account you can order complimentary envelopes, paks, poly bags, boxes and tubes for expedited FedEx services, after logging in at fedex.com.
- UPS: supplies such as UPS Express boxes and envelopes are ordered on ups.com with a UPS.com username. Under the Customer Supplies Policy update of November 2025, new customers get an initial allocation and continued access depends on shipping activity; some accounts can order only general supplies, not those meant for UPS Express shipments.
- DHL Express: DHL supplies packaging free of charge to account holders, ordered with the account number.
What size box keeps shipping costs lowest?
The smallest box that fits the item plus its padding is usually cheapest, because carriers charge large, light boxes by dimensional weight.
For Priority Mail, a box over 1,728 cubic inches is priced on length times width times height divided by 139 if that is higher than its actual weight. USPS Ground Advantage packages over 1 cubic foot may also get dimensional weight charges, with a maximum of 70 lbs and 130 inches in combined length and girth. The math is explained in how to calculate dimensional weight and cubic rates.
There is also a floor: a USPS parcel must be large enough to hold the shipping label, postage and any required markings on one side without bending or overlapping.
What types of small shipping boxes are there?
Most small shipments go in single-wall corrugated cardboard boxes; heavier, fragile or perishable goods need stronger or insulated boxes.
- Corrugated cardboard boxes: the standard shipping box. Besides cubes and rectangles they come as tubes and triangular boxes, and can be custom made to fit a product.
- Heavy-duty and moving boxes: thicker boxes for heavy or delicate goods, such as electronics or glassware, packed with cushioning foam.
- Insulated boxes: cardboard boxes with a foam liner that helps keep food and other perishables at a steady temperature.
- Poly mailers and padded mailers: often cheaper than a box for soft or flat items such as clothing.
How can you spend less on shipping boxes?
- Buy the sizes you ship most in bulk packs and compare the price per box.
- Use free Priority Mail boxes only when you really ship Priority Mail; for ground services, buy plain boxes.
- Pick the smallest box that fits the item and its cushioning to avoid dimensional weight.
- Switch soft goods to poly mailers.
- Do not save on quality for breakables: a box that fails costs more than the box. See the packaging guidelines and tips.
Once the box is sorted, the postage is the bigger cost. Shipixy gives discounted UPS, FedEx and USPS rates of up to 75% with no subscription fees. Compare prices in the Shipping Calculator or browse more packaging and label guides.
Sources
All sources were checked on October 25, 2026. Carriers change their rules and prices; the official pages below always win.
- USPS FAQ: Free shipping supplies (ordering, delivery, restrictions)
- USPS Postal Store: free shipping supplies
- USPS Domestic Mail Manual 601.6.1: USPS-produced packaging
- USPS Domestic Mail Manual 123: Priority Mail prices, Flat Rate and dimensional weight
- USPS Domestic Mail Manual 101: minimum parcel size
- USPS: Ground Advantage
- FedEx: packing and free packaging with your FedEx account
- UPS: order shipping supplies and Customer Supplies Policy
- DHL: prepare your shipment (packaging for account holders)
- Uline: corrugated boxes
- eBay Shipping Supplies store
