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Royal Post 4-State Barcode
User Guide > How to Work with... > Barcodes > Supported Barcode Types > Royal Post 4-State Barcode

The United Kingdom has implemented a new 4-state barcode referred to as the Royal Mail 4-State Customer Code (RM4SCC).
An example:

This barcode type is used by the Royal Post. It encodes 5, 6, or 7 character post codes along with a two character Delivery Point Suffix (DPS). A checksum character is included to verify the barcode read.