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Quick Service Guide 201a
Discount Letters
Designing Letters and Cards for Automated Processing

January 2006
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Letter-size mail and card-size pieces meeting the applicable automation standards are entitled to automation rates. This Quick Service Guide summarizes the standards for mail with 100% delivery point barcodes and mail without barcodes processed on USPS optical character readers (OCRs).


Physical Standards (201.3, 708.4)

Must meet all physical standards in 201.3.
Shape: rectangular.
Aspect ratio from 1.3 to 2.5 (201.3.3).

  • 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 cards at 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, 1/4 inch thick.

Maximum Weight:

  • First-Class Mail Machinable Presorted—3.3 ounces (0.2063 pound).
  • First-Class Mail Automation—3.3 ounces (0.2063 pound)1.
  • Periodicals Automation—3.3 ounces (0.2063 pound)1.
  • Standard Mail Machinable Presorted—3.3 ounces (0.2063 pound).
  • Standard Mail Automation Regular—3.5 ounces (0.2188 pound)1.
  • Enhanced Carrier Route High Density and Saturation—3.5 ounces (0.2188 pound)1.
  • Enhanced Carrier Route Automation—3.5 ounces (0.2188 pound)1.

1. Heavy letters over 3 ounces must bear an address block delivery point barcode under, be part of a 100% delivery point barcoded mailing, and be prepared in a sealed envelope. Heavy letters may not contain stiff enclosures or be prepared as a self-mailer or booklet-type mailpiece.


  • Polywrap, polybag, and shrinkwrap.
  • Clasps, strings, staples, buttons, or protrusions that might impede or damage the mail or mail processing equipment (201.3.4).

Other machinability standards:

Pieces with delivery point barcodes must meet all standards in 708.4:

  • Format of barcode bars (e.g., dimensions and spacing, 708.4.2).
  • Minimum clearance around barcode for barcodes printed on a mailpiece or label: 1/8 inch on left and right sides; 1/25 inch above and below barcode.
  • Placement of address block barcode, lower right barcode, or barcode within a window: see reverse.
  • Reflectance standards for barcode and portion of mailpiece on which barcode is printed (708.4.3).

For the specific DMM standards applicable to this category of mail, consult the DMM sections referenced above and the general sections within each DMM module.


Physical Standards for Automation-Compatible Mail (201.3)

This graphic describes the physical standards for automation-compatible mail as described in the text below.

Barcode Location: Delivery Point Barcode either within address block or within barcode clear zone in lower right corner of mailpiece (202.5).

Address Block Barcode: (202.5) Within address block (shown by dashed lines) must be:

  • Rightmost bar—at least 1/2 inch from right edge of the mailpiece.
  • Leftmost bar—less than 10-1/2 inches from right edge, and at least 1/2 inch from the left edge.
  • Top of each bar—less than 4 inches from bottom edge of mailpiece.
  • Bottom line in address block including barcode—at least 5/8 inch from bottom edge of mailpiece.

Recommended Address Placement: On a letter-size piece, the recommended address placement is within the optical character reader (OCR) read area, which is a space on the address side of the mailpiece defined by these boundaries (202.2.1):

  • Left: 1/2 inch from the left edge of the piece.
  • Right: 1/2 inch from the right edge of the piece.
  • Top: 2-3/4 inches from the bottom edge of the piece.
  • Bottom: 5/8 inch from the bottom edge of the piece.

Envelope Window: 1/8 inch —minimum clear space between barcode and right and left edges of window. 1/25 inch —minimum clear space between barcode and top and bottom edges of window. Clear space must be maintained when insert is moved to its full limits in each direction within envelope (202.5).

For Barcode in Lower Right Corner Location: Leftmost bar between 4-1/4 inches and 3-1/2 inches from right edge (202.5).

Barcode Window: If the barcode is printed on an insert to appear through a window in the lower right corner, see 202.5. For barcode placement and window dimensions, see 202.5.9.

Barcode Skew: The combined effects of positional skew (slant or tilt of the entire barcode baseline) and rotational skew (slant or tilt of the individual barcode bars) for a barcode on a card-size or a letter-size piece must be limited to a maximum rotation of the bars of ±5 degrees from a perpendicular to the bottom edge of the piece. The individual bars of a barcode must not shift (be vertically offset) more than 0.015 inch from the average baseline of the barcode (708.4.4.1).


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