2-8 Barcode Requirements

2-8.1 Basic Information

Privately printed domestic forms and labels must use USS Code 128 barcode symbology. The barcode represents the unique Package Identification Code (PIC), which comprises four fields totaling 20 characters. The PIC also appears in human-readable characters directly below the barcode.

As shown in Exhibit 2-8.1, barcode elements include the following:

1. Start Code: All barcodes must begin with Start Code C. The start character does not appear in the human-readable presentation and is not manually keyed or transmitted.
2. Service Type Code (STC): This two-digit number identifies the type of product and service used for each item (see 2-8.5.2).
3. Customer ID: This is the nine-digit DUNS number, which uniquely identifies business entities at specific physical addresses. Customers generating mailings at multiple locations must use the DUNS number appropriate for each mailing location.
4. Eight-Digit Sequential Number: Customers assign their own eight-digit sequential number, which must remain unique for each Service Type Code for at least 2 years in order to ensure that it identifies only one mailpiece.
5. Check Digit: A check digit is a digit added at the end of a sequence of numbers to validate the authenticity of the numbers. It is required for all customer-generated extra services forms and labels to detect errors resulting from manual data entry or errors from transmitted data. The algorithm for calculating the check digit appears in 2-8.5.3.

USS Code 128 barcodes for privately printed PS Forms 3800, PS Forms 3813-P, Labels 200, and PS Forms 3804 use weighted MOD 10 and MOD 103 check digits. The weighted MOD 10 check digit that follows the final digit of the eight-digit sequential number (reading from left to right) is considered a data element, and it must appear in human-readable form so that it is transmitted as data. The MOD 103 check digit, inherent in the USS Code 128 symbology, precedes the final Stop Code. It must not appear in human-readable form so that it is not transmitted as data.

6. Stop Code: All barcodes end with a Stop Code. The Stop Code does not appear among the human-readable numbers below the barcode, and it is not manually keyed or transmitted.

Note: Elements b–f make up the PIC.

Exhibit 2-8.1 

USS Code 128 Barcode Symbology