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What are Postcodes in the UK and internationally?

A UK postcode (also known in various countries as post code, postal code or zip code) is an alpha-numeric code which sits at the end of a postal address for the purpose of sorting mail.

How does a Postcode work?

The first part of a postcode - the "outcode" - identifies the postal district, i.e. SW is South West London. The second part - the "incode" - depicts the delivery points within that postal district that the local Royal Mail Delivery Office serves. There are about 15 delivery points per postcode.

Why are Postcodes important?

A postcode helps you find a full address. With a full and accurate address, you can send post to the correct location, helping you to:

  • Save time and money by reducing inaccurate mailings
  • Improve customer satisfaction by communicating with them quickly.
  • Build brand perception by removing embarrassing errors.
  • In terms of Data Quality, postcodes can help by ensuring fast and accurate capture of both UK and international addresses through Address Capture Tools.

How can Postcode validation help you?