Barcode Xpress for .NET Framework v13.9 - Updated
Intelligent Mail
Supported Barcode Types > Barcode Types > Intelligent Mail

The Intelligent Mail barcode is a fixed-length, numeric 1D barcode with a CRC (Cyclic Redundancy Check) checksum for error detection.

Example Barcode

The following example barcode encodes the information 44123123456123456789 as an Intelligent Mail barcode:

Intelligent Mail


Intelligent Mail barcodes are fixed-length at 65 bars. Those 65 bars encode 20, 25, 29, or 31 digits of information, as zip codes are variable-length (0, 5, 9, or 11 digits).

Barcode Breakdown

A Intelligent Mail barcode has 5 sections.

  1. BI (Barcode Identifier) - 2-digit identifier assigned by the Postal Service.-digit 2 must be between 0 and 4 (inclusive).

  2. STID (Service Type Identifier) - 3-digit identifier assigned by the Postal Service for services requested for the mail.

  3. MID (Mailer ID) - 6- or 9-digit identifier assigned by the Postal Service that identifies the customer. 6-digit MIDs cannot begin with a 9, and 9-digit MIDs must start with a 9.

  4. Serial Number - 6- or 9-digit value to establish uniqueness. This value is 6 digits if a 9-digit MID is used, and vice-versa.

  5. Routing Code - 0, 5, 9, or 11-digit code for routing the mail to its final delivery point.

Managing Organization

The Intelligent Mail barcode is governed by USPS-B-3200. 1

Similar Barcode Types

The Intelligent Mail barcode is also known as the "USPS OneCode Solution" or "USPS 4-State Customer Barcode" (abbreviated "4CB", "4-CB", or "USPS4CB").

Barcode Variants

Intelligent Mail barcodes are able to encode PostNet and Planet barcodes into a single barcode. 1

Related Barcodes

Intelligent Mail barcodes are similar to other 4-state barcodes that are common among postage organizations (e.g. Royal Post 4-State, Australia Post 4-State).


  1. "Intelligent Mail Barcode 4-State Specification." USPS, USPS, 20 Apr. 2015,

For additional background and use-case information see our Intelligent Mail barcode page.
For more information, see the Barcode Xpress SDK product page or try our online demos.

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