Understanding how to read a UK postcode can be a handy skill, whether you’re a local resident, a visitor, or simply interested in British geography. Postcodes, also known as postal codes, are used to sort and deliver mail efficiently. They are alphanumeric codes that consist of two parts: the outbound code and the inbound code.
Postcodes in the UK were introduced in 1959 and are managed by the Royal Mail. They are hierarchical and designed to help the postal service route mail quickly and accurately. Let’s dive into the world of UK postcodes and learn how to read and understand them.

Understanding the Structure of a UK Postcode
The structure of a UK postcode is quite straightforward once you understand the basics. It consists of two parts: the outbound code and the inbound code, separated by a space.
The outbound code typically consists of one or two letters followed by one or two digits. It represents a large geographical area, such as a city or a town. The inbound code usually consists of one digit followed by two letters. It represents a smaller area, like a street or a group of streets.
Outbound Code
The outbound code is the first part of the postcode. It’s often referred to as the ‘outward code’ or ‘outcode’. This part of the postcode helps the postal service sort mail to the correct delivery office. It covers a large geographical area, usually a city or a town.
For example, in the postcode ‘BN1 1AA’, ‘BN1’ is the outbound code. It represents the town of Brighton in East Sussex. If you’re sending a letter to Brighton, using ‘BN1’ ensures that your letter reaches the correct delivery office.

Inbound Code
The inbound code is the second part of the postcode. It’s often referred to as the ‘inward code’ or ‘incode’. This part of the postcode helps the postal service deliver mail to the correct address within the outbound code’s area. It covers a smaller geographical area, usually a street or a group of streets.
Using the same example, ‘1AA’ is the inbound code in ‘BN1 1AA’. It represents a specific area within Brighton. If you’re sending a letter to a specific address in Brighton, using ‘1AA’ ensures that your letter reaches the correct delivery address.
Postcode Districts and Sectors
UK postcodes are further divided into districts and sectors. A postcode district is the largest division, represented by the outbound code. It covers a large geographical area, such as a city or a town. A postcode sector is a smaller division, represented by the inbound code. It covers a smaller geographical area, such as a street or a group of streets.

For instance, in the postcode ‘BN1 1AA’, ‘BN1’ is the postcode district, and ‘1AA’ is the postcode sector. The postcode district ‘BN1’ covers the town of Brighton, while the postcode sector ‘1AA’ covers a specific area within Brighton.
Postcode Districts
Postcode districts are the largest division of UK postcodes. They are represented by the outbound code and cover a large geographical area, such as a city or a town. There are currently 124 postcode districts in the UK, each with its own unique two-letter code.
For example, ‘BN’ represents Brighton and Hove, ‘EC’ represents London, and ‘Glasgow’ is represented by ‘G’. Each postcode district is further divided into postcode sectors.
Postcode Sectors
Postcode sectors are a smaller division of UK postcodes. They are represented by the inbound code and cover a smaller geographical area, such as a street or a group of streets. There are currently 2,812 postcode sectors in the UK, each with its own unique three-character code.

For instance, ‘1AA’ is a postcode sector within the ‘BN1’ postcode district. It represents a specific area within Brighton. Each postcode sector is further divided into postcode units, which represent individual addresses.
Understanding how to read a UK postcode can be incredibly useful, whether you’re sending a letter, planning a route, or simply curious about British geography. With this knowledge, you can navigate the UK postal system with ease. Happy exploring!





















