The Intelligent Mail^® barcode (formerly known as the 4-State Customer Barcode) is the next generation of USPS^® barcode technology used to sort and track letters and flats. Intelligent Mail^® barcode technology, among other things, combines the capabilities of the POSTNET barcode and the Planet Code^® barcode into one unique barcode.

Frequently Asked Questions
Get answers to most frequently asked questions.

Steps to Create the Intelligent Mail Barcode
Handout with high-level step-by-step instructions on how to use the Intelligent Mail® barcode. Learn about the key components and what you need to consider before creating the barcode.

Resource Guide
Get background information and learn about the challenges and advantages of using Intelligent Mail^® barcode. The document also talks about the barcode construct, its symbology and print specifications.

Intelligent Mail Barcode Specification
Learn about the data content to be encoded, encoding rules to produce bars from data fields, physical dimensions of printed barcodes, and physical limitations on printing. The specification document (USPS-B-3200) also covers how the encoding and decoding algorithms work and provides code snippets written in C.

Mailer ID Application
Obtain instructions and application materials to request your Mailer ID for use in the Intelligent Mail^® barcode. The Mailer ID application process describes the steps for contacting your local Business Mail Entry Unit (BMEU) or Mailpiece Design Analyst (MDA).

OneCode ACS™
Learn how the process works, the features available, and mailer requirements to receive electronic address corrections using the Intelligent Mail^® barcode.
Downloadable OneCode ACS application and fulfillment access forms.

OneCode Confirm™
Learn about the Intelligent Mail^® barcode format for OneCode Confirm by reviewing the Confirm Service Featuring OneCode Confirm User Guide (Pub. 197). For more information on the Confirm^® service, please call the Confirm Customer Help Desk at 800-238-3150, option 1 or visit https://mailtracking.usps.com.

MASS™
Information regarding Multiline Accuracy Support System (MASS™) certification.

Videos and Presentations
These videos and presentations contain information regarding the Intelligent Mail^® barcode. They were introduced at the National Postal Forum.

Online Encoder/Decoder
Use this online tool to quickly Decode (convert a sequence of bars into meaningful tracking and delivery point ZIP information) or Encode (generate a barcode based on tracking and delivery point ZIP information) the Intelligent Mail^® barcode.

List of Intelligent Mail Barcode Resources
Get information about the tools and applications available to you from the Postal Service as well as from vendors for creating and validating the Intelligent Mail^® barcode.

OneCode ACS™ Sample Brochure

The Postal Service provides software support for 24 combinations of language environments (C, Java 2, COBOL, and PL/1) on 9 unique platforms (z/OS, VSE/ESA, OS/400, AIX, Linux, Solaris, HP/UX, Mac, and Windows). For printing Intelligent Mail® barcodes in a production environment, a variety of Intelligent Mail® barcode fonts are available for 5 major production printing environments: AFP (MVS, AS/400, VM, VSE), HP PCL, PostScript, Xerox Metacode, and TrueType. These resources are available for registered RIBBS users. Please click here to register for a username and password or contact the U. S. Postal Service National Customer Support Center at 877-640-0724 or send an email to onecodesolution@usps.gov.

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