How to Find a UK Postcode

The most dependable way to find a UK postcode is to look up the full address in the postcode finder of Royal Mail, the national postal operator. That finder is based on the operator's address database, so it reflects what couriers and sorting systems actually use.

Looking up a postcode

Open the postal operator's postcode or address lookup, enter the house number or name, and the street and town. The tool returns the matching postcode. Enter the address as precisely as you can, because many streets repeat across towns.

If you start from a postcode and need the address, the same lookup lists the properties inside that postcode. This is a quick way to confirm which building name or number belongs to which postcode.

Other places to check

• Previous letters, utility bills or official correspondence addressed to the property.
• The delivery address saved in an account with a trusted retailer.
• The council or local authority, which holds records of property addresses.
• A neighbour or a landlord, for shared buildings and flats.

Verifying the result

A pattern that looks right is not proof. Compare the returned postcode with the rules in UK postcode format explained and check that the town and street match. If the lookup returns several properties, make sure you chose the one with the right number or name.

Be careful with look-alike characters: the letter O and the digit 0, and the letter I and the digit 1, are the most common sources of a wrong postcode.

If you are unsure

• Do not guess a postcode. A near miss can send a parcel to a different street.
• Ask the property owner or occupier to confirm in writing.
• For new or unusual properties, such as converted barns, caravan sites or rural buildings, check whether the building is recorded under a different name.
• Provide a short note on how to reach the entrance.

Adding an exact-location code

For hard-to-find properties, a UPCS code can be added alongside the postcode. Choose the point on the UPCS map and use the generated code, which starts with GB (placeholder: GB-XXXX-XXXX). It is not a postcode and the postal operator does not use it, but anyone with the code can open the location on a map. Read more in the UK overview and in delivery and addressing challenges.