E-commerce News and Insights | Nov 10, 2021

Why Free USPS Priority Mail Boxes Are Smaller But Still Effective

Hasan Nabulsi

As we enter the busiest time of the year for many in the e-commerce industry, it’s important for carriers to maximize their output to meet customer demand. One way the United States Postal Service is doing this is by adjusting the size of their free USPS Priority Mail boxes.

The new sizes were originally rolled out in the last week of September. However, e-commerce merchants were allowed to use the Priority Mail boxes they already had until they ran out.

With more and more holiday shopping orders rolling in this month, stocking up on packaging supplies will be critical. We’ll explain what these new sizes mean for your holiday shipping processes and beyond.

Why Are Free USPS Priority Mail Packages Getting Smaller

There are likely two primary reasons for USPS Priority Mail packages getting smaller.

The size decrease for Priority Mail poly bags allows them to be more compatible with sorting equipment. This helps automate the process for USPS so that they can sort faster and stay organized, especially during a time of year like now.

The other reason is to maximize the space available within their transportation vehicles. Every inch counts when it comes to logistics, and with holiday shipping volumes estimated to reach all time highs, getting the most out of every delivery will be vital to getting gifts delivered on time.

It is worthy to note that these package size differences will be put in place indefinitely, so the effects on your e-commerce business will last even after the holiday rush slows down.

New Sizes For USPS Priority Mail Boxes

The size differences are now being seen across two different envelopes and six different boxes. The sizes themselves range from as little to ⅛” to 2 1/2” as seen below.

Item/Service (SKU) Previous Outer Dimensions New/Current outer Dimensions Net Change In Size
Priority Mail Tyvek Envelope (EP14) 15 and ⅛” Length times 11 and ⅝” Width 15” Length times 11 and ⅝” Width ⅛” in Length
Priority Mail APO/FPO Tyvek Envelope (MILIPAC) 15 and ⅛” Length times 11 and ⅝” Width 15” Length times 11 and ⅝” Width ⅛” in Length
Priority Mail Large Flat Rate Box (LFRB) 12-¼” Length X 12-¼” Width X 6” Height 12-¼” Length X 12” Width X 6” Height ¼” in Width
Priority Mail APO/FPO Large Flat Rate Box (MILIFRB) 12-¼” Length X 12-¼” Width X 6” Height 12-¼” Length X 12” Width X 6” Height ¼” in Width
Priority Mail (0-1092 Box) 13-11/6” Length X 12 ¼” Width X 2-⅞” Height 13-11/6” length X 12” Width X 2-⅞” Height ¼” in Width
Priority Mail (0-1095 Box) 15-⅝” Length X 12-½ Width X 3-⅛” Height 15” Length X 12” Width X Height 3-⅛” ½” in Width

⅝” in Length

Priority Mail Regional Rate Box B (RRB-B2) 16-¼” Length X 14-½” Width X 3” Height 15” Length X 12” Width X 3” Height 1-¼” Length

2-½” Width

Priority Mail (Box 7) 12-¼” Length X 12-¼” Width X 8-½” Height 12-¼” Length X 12” Width X 8-½” Height ¼” in Width

How The New USPS Priority Mail Box Sizes Affect E-commerce Merchants

These size changes in all likelihood will not and have not affected most e-commerce merchants.

With sizes shrinking by just a fraction of an inch for most Priority Mail packages, your products should still fit in the same.

One difference may lie in how much you stuff these boxes in order to protect your products. With the smaller dimensions, you are able to use less stuffing per package, which could save you money if you are shipping a lot of your products through USPS Priority Mail.

How To Get USPS Priority Mail Boxes For Free

There are two ways to get USPS Priority Mail boxes for free for your business. The first way is to head into your local post office and purchase/pick up boxes from there. However, e-commerce merchants don’t always have the time to commute and wait in line to get these supplies.

By going to the USPS Store online, you can order boxes and envelopes, and have them delivered to your place of business for free. Some packages come in packs of 10, while others come in packs of 25. The maximum permitted quantity of packs you can order at one is 20.

Why Free USPS Priority Mail Boxes Are Still Effective

Using free USPS Priority Mail boxes is still an effective way to ship your products because, even though the size of the box has changed, the trusted USPS service levels and competitive rates are still in place.

By shipping with USPS, you’ll have the ability to ship out your products to customers at every residential address within the U.S. With Flat Rate boxes you’ll even be able to ship heavier products without having to worry about paying for any additional weight as long as it fits.

On top of that, Shippo customers will still be able to purchase discounted USPS shipping labels  for USPS  – up to 90% off retail rates – no matter which service they choose to use. Shippo customers can also compare USPS Priority Mail rates as well as rates from other top carriers.

Sign up for your free Shippo account today and start creating USPS shipping labels for your Priority Mail deliveries in minutes.

Hasan Nabulsi is the Content Marketing Manager at Shippo.

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