Once mailers have selected their service(s), received a MID, and devised a unique serial number strategy, they are ready to put the five fields together to form the 20- to 31-digit string, encode it to 65 characters, and convert the 65-character string using the IMb font to form the 65-bar IMb as in the example below. On letters, the IMb can be placed in the address block or in the barcode clear zone. On flats, it can be placed on the address side at least 1/8 inch from the edge of the piece.
Learn more about the IMb at https://postalpro.usps.com/mailing#cat-subsection-2.
EXAMPLE: STID of 270 (First-Class Mail®, Intelligent Mail Full-Service option, with IMb IV service, no address correction), MID 123456, uniquely identified by Serial Number 200800001, going to ZIP Code 98765-4321(01), is encoded like this:
Digit String: 0027012345620080000198765432101
uIMb encoder uEncoded string (T=Tracker, F=Full Bar, A=Ascender, D=Descender): TTFAFDADTFFFADTAFAFTTDATDFAAFTDAFDFDFDATFDFTDDDDFADFFDADDTDDTTDAT
u IMb font u IMb:
To learn about certified mail service providers (MSPs), please visit https://postalpro.usps.com/node/3816 and https://postalpro.usps.com/mailing/election-political-mail. The latest lists of certified MSPs can be found on these pages under Featured Resources.
