USPS

USPS Flat Rate Boxes & Pricing

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What are USPS Flat Rate Boxes?

USPS Flat Rate Boxes are just that - boxes with flat postage rates, no matter how heavy the package is. If you're shipping heavy, small items, Flat Rate Boxes are the best bang-for-your-buck option. Keeping a supply of these around your fulfillment operations can cut your shipping costs by 50%.

All of these packages are supported through the EasyPost API by using our predefined packages. So it's easy to set up internally and start collecting savings from your Flat Rate Boxes as soon as you integrate with EasyPost.

How Much Do USPS Flat Rate Boxes Cost?

We've broken the pricing into the table below. Note: The rates below reflect USPS Commercial Plus Pricing, which is available when shipping via EasyPost. If you're interested in signing up for USPS Commercial Plus Pricing, contact us and we can set you up.

The following rates are based on pricing from January 21, 2018.

TypeSizeEasyPost Predefined PackagePrice
Letter Envelope12 1/2" x 9 1/2"FlatRateEnvelope$6.35
Gift Card Envelopes10" x 7"FlatRateGiftCardEnvelope$6.35
Window Envelopes10" x 5"FlatRateWindowEnvelope$6.35
Small Envelopes10" x 6"SmallFlatRateEnvelope$6.35
Padded Envelopes12 1/2" x 9 1/2"FlatRatePaddedEnvelope$6.90
Legal Envelopes15" x 9 1/2"FlatRateLegalEnvelope$6.65
Small Box8 11/16" x 5 7/16" x 1 3/4"SmallFlatRateBox$6.85
Medium Boxes11 1/4" x 8 3/4" x 6" or 14" x 12" x 3 1/2"MediumFlatRateBox$12.45
Large Box12 1/4" x 12 1/4" x 6"LargeFlatRateBox$17.10

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