If you are planning on sending mail with the popular Flat Rate boxes that are offered by the USPS, and you are wondering what the Flat Rate boxes shipping cost might be, this article can help you find the information that you are looking for. The USPS breaks down their Flat Rate box cost by using weight and zones.

There are nine different zones that USPS flat rate packages can pass through, with each zone representing a geo region that can result in a price increase based upon the flat rate box sizes and weight. The ninth zone is the costliest whereas the first zone is the most affordable. It’s also based upon the weight of the parcel being shipped, something that increases with size and weight, from 15 pounds, where it starts, all the way up to 25 pounds. Size does indeed also play a role. We’ll help you better understand, so keep reading.

Use this helpful shipping calculator to find out how much you stand to save with Flat Rate Select USPS discount pricing.


The easiest way to figure out what your Flat Rate boxes shipping cost will be is to use the calculator that’s provided by the USPS. This online calculator is free to use. All you have to do is enter the relevant information about your pending shipment. Before you buy your postage directly from the USPS, however, make sure you read the rest of this article to find out how you can get the lowest prices on postage on all your outbound USPS flat rate packages.

Introducing Flat Rate Select, a faster, easier and CHEAPER way to ship all your USPS Priority Mail packages… for LESS! Get connected to the best rates on all your Priority Mail package up to 20-pounds. Use your own boxes with no volume requirements. Check out the shipping calculator below to find out how much you could save.

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