Shape based rate structure first introduced by the USPS in 2007 to de-emphasize weight alone and incorporates weight with length, height, shape, and thickness of a mail piece. For instance, a 2 ounce letter will mail for $0.61, a 2 ounce flat for $1.05 cents, and a 2 ounce parcel for $1.39.  Since it is no longer all about the weight, choosing the best value envelope has a significant impact on the postage paid. 

For example; a 4 page document mailed flat in an envelope that measures 9 " x 12 " will cost $1.05 to mail.  Fold that document one time in half and send in a 6 1/8" x 9" and it becomes a letter that mails for $0.61. Tri fold that same 4 pages and place into a # 10 letter size envelope and again, the cost will be only $0.61; a 42% reduction over the large envelope!  You save on postage and because smaller envelopes are less expensive, you save on supply costs as well.

Other factors that can impact postage costs include adding rigid contents to envelopes and address orientation.  For more details go to pe.usps.com, Price List Notice 123 effective March 14, 2010, page 44 or call OMG, LLC and let us help you figure out your best cost saving option. (800) 207-4807. Click for PDF

Note: Flat-rate prices are available when material is sent in a USPS-produced Flat Rate Envelope or Box. When sealing a Flat Rate Box or Flat Rate Envelope, the container flaps must be able to close within the normal folds. Tape may be applied to the flaps and seams to reinforce the container, provided the design of the container is not enlarged by opening the sides and the container is not reconstructed in any way. Weight restrictions for Domestic are 70 lbs. Weight restrictions for Priority Mail International are 4 lbs for the Flat Rate Envelope and Small Flat Rate Box; 20 lbs for the Medium/Regular and Large Flat Rate Boxes.

DOMESTIC Retail Online

Express Mail

Flat Rate Envelope $18.30 $17.40
12-1/2" x 9-1/2"

Priority Mail

Flat Rate Envelope 4.90 4.75
12-1/2" x 9-1/2"

Small Flat Rate Box 4.95 4.85
8-5/8" x 5-3/8" x 1-5/8"

Medium/Regular Flat Rate Boxes 10.70 10.20
11" x 8-1/2" x 5-1/2"

13-5/8" x 11-7/8" x 3-3/8"

Large Flat Rate Box 14.50 13.95
12" x 12" x 5-1/2"