Usps priority medium flat rate box dimensions

One of the challenges that often comes with utilizing flat rate boxes is the size. What is the USPS medium flat rate box size? How much can you fit in there without having any sort of problems come up in the process? And how can you use the box in an effective manner so that you don’t end up spending way too much on the process? Let’s take a look.

Measuring Up the USPS Medium Flat Rate Box Size

There are two main types of USPS Medium Flat Rate Box Size options. This is because this is the box option that many people choose for what they need to send. Most items are going to fit within one or the other, and the rate is affordable, while still getting the package to where it needs to go within a reasonable amount of time. The “Medium Flat Rate Box – 1” which is a top-loading box, has the following dimensions:

  • Inside of the box: 11″ x 8 1/2″ x 5 1/2″
  • Outside of the box: 11 1/4″ x 8 3/4″ x 6″

This box is squarer shaped and, because of that, you may have to be careful about which items that you are trying to put in the box.

The other box that they offer, referred to as the “Medium Flat Rate Box – 2” loads from the side, and it has different dimensions due to that variation. Here are the dimensions of that box:

  • Inside of the box: 14″ x 12″ x 3 1/2″
  • Outside of the box: 14″ x 12″ x 3 1/2″

You want to make sure that you take a look at the sizing before you decide on which USPS medium flat rate box size that you want to utilize. By having an idea as to the dimensions of the item that you’re going to be sending, you can know that you’re actually going to get it all taken care of and you won’t be missing out on anything in terms of space.

What Can People Usually Fit in The Medium Flat Rate Box?

No matter which type of box that you decide to utilize, you will find that there are a lot of things that you can fit into them. Many times, people will use these boxes to send off office supplies of all sorts. In other instances, you may be able to utilize the box to send small board games and other similarly sized items. It’s a roomy box and you can fit a lot of smaller objects in there if you need to do so.

The side loading box is for items that are flatter and take up more area in general. This box can usually fit a pair of shoes, depending on the size. Standard board games fit into this box (even though there is now a “board game box” that the USPS offers as well). Many people will also go ahead and utilize this box in order to send clothing, since it is a good sized for many shirts and such that may need to be folded in order to be sent to where they are headed.

Is It Worth the Cost of the Box?

Whether you get the top-loading or the side-loading option, you will find that the cost for these boxes is actually quite reasonable for the two to three day priority mail options that you have with them. As of February, 2017, the cost of shipping either of these medium flat rate boxes is at $13.60. This rate is, obviously, for items that are less than 70 pounds, as it the case with many of these options. The fact of the matter is, if you’re attempting to ensure that you get everything necessary sent for a low cost, it can be worth your time and effort to go ahead and use this instead of the other shipping options that may be out there.

USPS Flat Rate Boxes

You know that saying, “if it fits, it ships”? This is the service they’re referring to.

As long as the contents of the box weighs less than 70 lbs and you can close the box for secure shipment, the price will not change. 

Usps priority medium flat rate box dimensions
All of the supplies shown below are available in the Mail Services, and are free for campus business (you’ll have to pay for postage when shipping, but the box or envelope is free).

USPS carries many varieties of non-flat rate boxes and upon request, Mail Services can keep them in stock. Simply call us to get more information or visit our supplies page to order from us online!

Please note: All of these prices are for domestic shipping only. For information about shipping internationally, including prices and restrictions, see my International Shipping page.

Also, please do not ship cats in boxes.

New prices effective as of 11/19/2021!

 
Usps priority medium flat rate box dimensions
Small Flat Rate Envelope

Price: $7.70
Size: 10” x 6”, slightly larger than a regular #10 envelope. You could probably fit a smaller greeting card in it as well

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Flat Rate Envelope

Price: 8.70
Size: 12” x 9.5”, large enough for a regular size manila envelope

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Legal Size Flat Rate Envelope

Price: $9.00
Size: 15″ x 9.5″, a good choice for all legal size documents

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Padded Flat Rate Envelope

Price: $9.30
Size: 12.5” x 9.5”, large enough for a regular size manila envelope

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Small Flat Rate Box

Price: $9.20
Size: 8.5″ x 5.5″ x 1.5″, approximately the same size as a VHS tape (for those of you who have seen those firsthand)

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Medium Flat Rate Box

Price: $16.25
Size: 11″ x 8.5″ x 5.5″, great for shipping care packages, books, whatever.

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Medium Flat Rate Box (2)

Price: $16.25
Size: 13.5″ x 11.5″ x 3″, good for shipping notebooks, books, t-shirts, chocolates, promises you don’t intend to keep…

Weight limit: 70lbs domestically, 4lbs internationally.

 
Usps priority medium flat rate box dimensions
 
Large Flat Rate Box

Price: $22.65
Size: 12″ x 12″ x 5.5″

Weight limit: 70lbs domestically, 4lbs internationally.

Is it cheaper to use a flat rate box or your own box?

As we mentioned above, combining your own custom packaging with the right USPS service is often more cost-effective than using flat-rate boxes. One such option is taking advantage of cubic pricing. Priority Mail cubic pricing is a more efficient USPS service for shipping small packages that weigh up to 20 pounds.

What is Priority Mail Medium Flat Rate box?

Priority Mail Flat Rate Products.

What are USPS Priority Mail dimensions for packages?

An oversized letter or package needs to be measured to see if it fits within guidelines. The dimension guidelines for the machinability of a Priority Mail item are 27 inches x 17 inches x 17 inches. Maximum Weight = 70 pounds (lower weight limits apply to commercial plus cubic and some APO/FPO/DPO mail).

Can I use my own box for medium flat rate box?

The Priority Mail Medium Flat Rate Box comes in two sizes: Use your own box for a custom size that fits your products, or USPS offers two free "mailing boxes" that are the cubic 0.4 size: Priority Mail Box - 1095 | 15-1/4" x 12-3/8" x 3" | Cubic Tier 4.