USPS Priority Mail Express Flat Rate

What is Priority Mail Express Flat Rate?

Priority Mail Express Flat Rate is a fast, overnight shipping service provided by the U.S. Postal Service (USPS) that features one low flat rate for the delivery of packages or envelopes. The maximum weight for this mail class is 70lbs. Priority Mail Express Flat Rate mailpieces can be delivered to virtually all U.S. addresses such as military locations and PO Boxes. This mail class is a great option for mailing and shipping business and legal documents, manuscripts, clothing, books, boxed jewelry, office supplies and shoes.

Priority Mail Express Flat Rate includes special features at no cost including tracking, package pickup, signature proof of delivery and insurance coverage up to $100. In addition, Priority Mail Express Hold For Pickup service is available for free and ensures that your shipment is held at a Post Office location for pickup. You can also obtain additional USPS special services for a fee, such as Saturday and holiday delivery, Return Receipt, Collect on Delivery, and steeper insurance coverage. When purchasing postage and shipping online, Priority Mail Express Flat Rate includes free USPS Tracking.

Try us out for 4 weeks! Get $5 in free postage

(to use during your trial).

Try us out for 4 weeks! Get $5 free postage

(to use during your trial)

Try us out for 4 weeks!

Get $5 free postage

(to use during your trial)

How to use Priority Mail Express Flat Rate?

Using Priority Mail Express Flat Rate is very simple. As long as your package is not heavier than 70lbs., you will not need to weigh it.

When preparing to ship with Priority Mail Express Flat Rate, you can order the free envelopes or boxes through the USPS website or pick these up at the Post Office. Ensure that your item fits securely within the envelope or box and that the self-adhesive flaps close and adhere to the shipment. Additional tape can be applied for more support. The contents of your shipment should not alter the shape of the envelope or box being used. This guideline includes and is not limited to the reconstruction of the envelope or box as well as opening the sides to create space. Your shipment must contain postage or a shipping label plus delivery and return addresses.

Using Priority Mail Express Flat Rate with Stamps.com

Here are Priority Mail Express Flat Rate prices and package dimensions along with the rates offered by the USPS and Stamps.com:

Priority Mail Express Flat Rate
Priority Mail Express Flat Rate Options Maximum Weight Outside Dimensions Post Office™ Rate Stamps.com Rate
Flat Rate Envelope up to 70 lbs. 12 ½″ x 9 ½″ $19.99 $18.11
Legal Flat Rate
Envelope
up to 70 lbs. 15″ x 9 ½″ $19.99 $18.11
Padded Flat Rate
Envelope
up to 70 lbs. 12 ½″ x 9 ½″ $19.99 $18.11
Flat Rate Box
Top Loading
up to 70 lbs. 11 ¼″ x 8 ¾″ x 6″ $44.95 $44.95
Flat Rate Box
Side Loading
up to 70 lbs. 12″ x 3 ½″ x 14″ $44.95 $44.95
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Stamps.com customers have the opportunity to save when using Priority Mail Express Flat Rate. All customers receive a 9% postage discount off of retail rates when mailing or shipping with any Priority Mail Express Flat Rate Envelope. This discount does not apply to Priority Mail Express Flat Rate Boxes. The Stamps.com software instantly calculates pricing and discounts, saving its customers valuable time. To process Priority Mail Express Flat Rate shipments and receive discounts, customers simply click to the Packages section of the Stamps.com software and submit their shipment information. Customers also have the option to order free Priority Mail Express Flat Rate packaging at the online Stamps.com Store


Try Stamps.com for 4 weeks!

Every new customer account starts with:

  • Free 5 lb. Digital Scale*, connects via USB
  • 4-week trial
  • $5 in free postage to use in trial period
  • Free Supplies Kit including postage labels
  • Additional $10 postage coupons to use after trial
    *pay only S&H fee