Number of UK Postcodes

The United Kingdom has approximately 1.8 million postcode units (as of 2023).

Structure

Format: A(A)9(9) 9AA (e.g., SW1A 1AA).
Outward code (area + district) → ~3,000 areas.
Inward code (sector + unit) → individual addresses (avg 15 per unit).

Management

Royal Mail maintains the Postcode Address File (PAF®); updated daily. Used for mail sorting, navigation, demographics, insurance, and more.