This is a list of postcode districts in the United Kingdom and Crown Dependencies. A group of postcode districts with the same alphabetical prefix is called a postcode area. All, or part, of one or more postcode districts are grouped into post towns.
Until 1996, Royal Mail required counties to be included in addresses, except for 110 of the larger post towns. For these "special post towns", the former postal county is shown in brackets below. Since 1996, counties are not required for any address.
Postcode district codes are also known as "outward codes".