Royal Mail Customer Barcode (also known as RM4SCC) is a barcode, used by British Royal Mail. It enables UK postcodes as well as Delivery Point Suffixes (DPSs) to be read by a machine at high speed.
The the barcode consists of a start character, the postcode, the Delivery Point Suffix (DPS), a checksum character, and a stop character. Valid characters are 0-9 and A-Z. Start and stop characters are: ( [ ] ) (they are added automatically as necessary)
Royal Mail offers significant (10 %) discounts for letters, labelled with machine readable Royal Mail Customer Barcode
There are strict guidelines governing usage of these barcodes, which allow for maximum readability by machines.