Automation Letters and Cards

If your letter-size mailpiece is machinable and displays the correct barcode, you may qualify for lower, "automation" rates. A letter or card meets automation standards and qualifies for automation rates if it meets the specific addressing, barcoding, and design standards.

Maximum weight:

First-Class Mail and Periodicals: 3.3 ounces.
Standard Mail: 3.5 ounces.

Shape: Rectangular.
Aspect ratio: (length divided by height) from 1.3 to 2.5

Dimensions:

Minimum: 3-1/2 inches high, 5 inches long, and either 0.007 inch thick if not more than 4-1/4 inches high and 6 inches long; or 0.009 inch thick if more than 4-1/4 inches high or 6 inches long, or both.
Maximum for First-Class Mail card rates: 4-1/4 inches high, 6 inches long, and 0.016 inch thick.
Maximum for letters and other cards: 6-1/8 inches high, 11-1/2 inches long, and 1/4 inch thick.

Length is the dimension parallel to the address as read.

All letter-size reply cards and envelopes (business reply, courtesy reply, and meter reply mail) provided as enclosures must meet the physical standards for automation letters and cards.

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