Size, Weight, and Shape Matters

Mail Services can help community members save time and money as they navigate the changing rules of the U.S. Postal Service, international requirements, and shipping guidelines. Feel free to consult with Mail Services before printing materials and planning large mailings.

Size Regulations

Letters

The U.S. Postal Service will accept nothing smaller than 3 1/2 inches by 5 inches. An 11-cent surcharge is added to pieces more than 6 1/2 inches by 11 inches or 1/4 inch thick.

Postcards

The maximum size for a postcard is 4 1/4 inches by 6 inches. Any card larger than this is charged as a letter. The minimum size is the same as for letters.

Barcodes

The U.S. Postal Service has restrictions on where printing may appear on envelopes in order to fit their automation equipment. The Barcode Clear Zone is the area where the barcode is printed. The area in the lower right corner 4 1/4 inch from the right edge and 5/8 inch up from the bottom edge must be kept clear. Neither words nor design may be printed or written in this area.

OCR Read Area

The OCR Read Area—the middle of the envelope that contains the address – must be clear of extraneous printing. Logos and return addresses in this area can cause mail to be returned to the sender.

Please check with Mail Services before ordering envelopes. Requirements for mailing change frequently, so even an established design may not pass current regulations.

Call Mail Services to discuss mailing matters between 8AM and 3PM, Monday through Friday, or fax a copy of a proposed design to 617-252-1552.