Glossary
Postcode
A postcode is an alphanumeric code used by Royal Mail to sort and route mail to a small group of addresses in the UK.
What is postcode?
A UK postcode, such as SW1A 1AA, identifies a small cluster of addresses, typically around fifteen. It is made up of an outward code and an inward code separated by a space.
Because postcodes are precise and hierarchical, they are widely used as a key for address lookup, delivery routing, and location analytics.
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Outward codeThe outward code is the first half of a UK postcode and identifies the postal district, for example SW1A in SW1A 1AA.Inward codeThe inward code is the second half of a UK postcode and pinpoints the delivery point, for example 1AA in SW1A 1AA.Postcode areaA postcode area is the one or two letters at the start of a postcode, such as M for Manchester or EH for Edinburgh.