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The advantage of Flat Rate is that regardless of how much you fit into the packaging, it’s allowable. There are times when USPS Flat Rate boxes are the cheapest way to ship. But, there are also times when standard Priority Mail, or other services, works better. Regardless, knowing how to use Flat Rate shipping options will end up saving you time and money on your shipping. USPS Flat Rate is a class of packaging that provides specific-sized boxes and envelopes for use with USPS Priority Mail services. They can be shipped anywhere in the US for one flat fee regardless of weight, so long as the parcel weighs fewer than 70 lbs. You can visit a USPS facility location or go to the USPS online store to order free USPS-branded flat-rate packaging. These supplies may be free, but it is required that you use them with their intended service.
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When Can I Not Use USPS Priority Flat Rate Boxes?
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USPS Flat Rate packaging CANNOT be used with standard Priority Mail services, First Class Mail®, Media Mail®, or with other carriers. They are only allowed for their designated Priority Mail Flat Rate service. How Much Does USPS Flat Rate Packaging Cost? If you try to use a Flat Rate box or envelope with a standard Priority service or any other service, the parcel will be returned or a post-billing correction will be sent to your postage account. Priority Flat Rate is the USPS’s one-size-fits-all packaging that lets you fit as much as you can into the box as long as it’s under 70 lbs.
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