The United States Postal Service’s Priority Mail service provides delivery of most items in 1 to 3 business days throughout the country, or 6 to 10 business days for international delivery. When sending your items, you have the option to choose flat rate shipping or to pay for the items by weight. The USPS provides free shipping materials for Priority Mail, though you are also free to provide your own packaging. Priority Mail Express provides expedited service for an additional fee.

Flat Rate Shipping

Shipping via USPS Priority Mail flat rate service allows you to send your item anywhere in the United States for a single price when you use the provided flat rate packaging. Items must weigh 70 pounds or less and fit into one of the flat rate shipping containers. The USPS provides a variety of flat rate envelopes and boxes free of charge that you can order online or pick up at your post office. Sizes range from 10-inch by 5-inch envelopes through 12 1/4 by 12 1/4 by 6-inch boxes; rates differ for the different sizes.

Other Shipping Options

If you choose to ship via Priority Mail in something other than flat rate packaging, you’ll pay a rate based on the weight of the package and the zone you are shipping to. You can use your own packaging or USPS non-flat-rate packaging, but the packages must be clearly marked as Priority Mail. The USPS provides free Priority Mail tape and stickers for this purpose. Packaging cannot measure more than a total of 108 inches when you add together the length and the girth – the distance around the widest part.

Additional Shipping Features

Priority mail comes with a tracking number that allows you to check the progress of your shipment, so you can tell when it arrives safely. It comes with insurance coverage up to $50, and you can buy additional coverage for most items. If you need to make a change to your shipment and discover the mistake early enough, it’s possible to intercept and redirect an undelivered Priority Mail item by requesting the Package Intercept service and paying the service fee.

Sending Your Items

Fill out the Priority Mail shipping slip either online or in person at the post office. You’ll need to know the recipient’s address, your return address and the value of the contents. If filling out the information online you’ll also need to identify which flat rate shipping package you are using or the actual weight and dimensions of the package. If you find you can get a better rate sending your package by regular Priority Mail instead of using flat rate shipping, cover the flat rate packaging with plain paper and tape it securely, then ship it via weight-based Priority Mail instead.