What Is USPS Flat Rate? (All You Need To Know)

As the cost of everything in the country goes up, so does the postage from the United States Postal Service, meaning shipping packages can get expensive. USPS has long sought to offer its customers more affordable shipping options.

One thing USPS has come up with: Flat-rate shipping. What is USPS Flat Rate? How can it save you money and time at the Post Office? I’ve got what you need to know right here!

What Is USPS Flat Rate In [currentyear]?

USPS Flat-Rate shipping is a service where free boxes and envelopes are provided by your local Post Office each ship for a given rate, up to a 70-pound max as of [currentyear]. The packages come in different shapes and sizes and ship via several services, including Priority Mail. Costs are competitive, especially for medium-sized heavy items.

To learn more about how USPS Flat Rate shipping works, how much it costs (and how much it can save you), and whether or not Flat Rate is even worth it for you or your business, keep reading!

How Does USPS Flat Rate Work?

Although it can appear complicated, USPS Flat Rate is quite simple when you know what’s going on.

Shipping Options

There are four USPS shipping services that have the Flat Rate option, including:

Priority Mail

This service delivers within one to three days, depending on the distance the package must travel. It includes USPS Tracking and $50-worth of insurance.

Also, there are seven different Priority Mail Flat Rate boxes to choose from, ranging from a 12.5” x 9.5” envelope to a two-foot-long rectangular box.

Moreover, there’s a special box for mailing to active-duty service members.

Priority Mail Express

USPS’s fastest domestic shipping option, Priority Mail Express, offers overnight or one-day shipping, depending on the distance.

However, this super-fast shipper accommodates Flat Rate envelopes only; the basic Flat Rate envelope, plus a Legal Flat Rate and a Padded Flat Rate.

Additionally, one major plus to this service is that delivery is guaranteed; if your Express Flat Rate envelope does not make it to the destination on time, you get a full refund.

Priority Mail International

For faster service than First Class International, Priority Mail International reaches its destination within six to ten business days.

That said, there are six different parcel types and sizes to choose from, including envelopes, a DVD box, and assorted small, medium, and large boxes.

However, for Priority Mail International, destination countries are organized into Price Groups.

For example, your Flat Rate price is determined by which box you choose and which Price Group your destination falls under.

Unfortunately, the weight limit for International Flat Rate shipping is lower than for domestic; some boxes have a limit of 20 pounds, while some are just four pounds.

Overall, our neighbor to the north, Canada, is currently the most affordable Flat Rate shipping destination.

Priority Mail Express International

Priority Mail Express International USPS

It can seem kind of crazy, but yes, USPS can reach many destinations around the world in just three to five days with Express International.

However, Priority Mail Express International only supports Flat Rate envelopes with a max weight of four pounds.

Moreover, there are eight different Price Groups, so again, the Flat Rate fee depends on the Price Group in which your destination country falls.

Shipping Boxes And Envelopes

Did you know that you can pick up Flat Rate boxes and envelopes at your local Post Office for free?

Yes, they’re free, and they are kept in stalls that stand outside of the area that gets gated off during closed hours.

That way, you can access them in the open lobby area at any time of the day or night.

But even better, if you don’t want to make the trip, you can order them online at USPS.com, and they’re not only free to “purchase,” USPS ships them to you for free, as well!

Labels And Postage

You have a few options for obtaining the actual postage label on your Flat Rate box or envelope.

First, you can bring your packaged parcel into the Post Office and have the teller at the counter take the shipping information and print it out then and there.

Also, you can print it on your own at home using Click N Ship at USPS.com, affix it to the parcel and even schedule a free pickup.

Or, you can create and pay for the label at home, bring the parcel to the Post Office and have them print the actual label there, which is a good option for people who don’t have a printer.

How Much Is USPS Flat Rate?

Flat Rate shipping for Priority Mail starts at just $8.95 for the basic Flat Rate envelope.

Further, the smallest box is $9.45; the largest costs $21.50 to ship, and a box heading for a military base or the embassy costs $20 to ship.

Also, Priority Mail Express Flat Rate envelopes start at $26.95 and only range up to $27.50 for the padded version.

Now, Flat Rate International shipping pricing is just a little bit trickier to calculate because each country’s destination falls under a Price Group category, which each has its own set Flat Rate.

Moreover, for a full price list of all USPS Flat Rate prices, check out this page.

Is USPS Flat Rate Cheaper?

There is one major factor to consider when figuring out if USPS Flat Rate is cheaper than any of the other shipping options.

For example, it comes down to your item’s size and weight combined. Is it small to medium-sized but heavy – like a small sculpture made from metal?

In this case, Flat Rate could be the best option for you because regular Priority Mail and Priority Mail Express get more expensive as the weight of the shipment increases.

Still, the easiest way to see if Flat Rate shipping will save you money is to plug the numbers into the USPS retail postage price calculator.

Is It Cheaper To Use A USPS Flat Rate Box Or Your Own?

To take advantage of USPS Flat Rate prices, you must use the free Flat Rate boxes provided by the Post Office.

Fortunately, you can pick those up in any Post Office lobby or order them online and have them shipped to you for free.

What Is The Difference Between USPS Priority Mail And Flat Rate?

USPS Priority Mail is a quicker shipping service than First Class Package, though not as fast or as expensive as Priority Mail Express.

With Priority Mail, customers can use their own boxes to ship, and postage is calculated based on the weight of the shipment (and sometimes, based on the size, too).

Further, Flat Rate is a shipping option that falls under the Priority Mail and Priority Mail Express services (and a few international services).

That said, it ships at the speed of the service chosen, but customers instead use Postal Service-supplied Flat Rate boxes for items up to 70 pounds in most cases and pay a set rate.

To know more, you can also read our posts on USPS Flat Rate envelope restrictions, how fast is USPS Flat Rate shipping, and what is USPS Regional Rate.


USPS Flat Rate shipping makes sending parcels more affordable and easier than ever.

That said, customers can get Flat Rate boxes for free at Post Office locations and even create and print labels at home – then schedule a free box pickup.

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Marques Thomas

Marques Thomas graduated with a MBA in 2011. Since then, Marques has worked in the retail and consumer service industry as a manager, advisor, and marketer. Marques is also the head writer and founder of QuerySprout.com.

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