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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.

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 disctrict that the local Royal Mail Delivery Office serves. There are about 15 delivery points per postcode.

A postcode helps you find a full address. With a full and accurate address, you can send post to the correct location, saving time and money, and improving customer satisfaction and brand perception.

Our postcode look up tools ensure fast and accurate capture of both UK and international addresses. Whether you capture customer addresses online via your website or over the phone, our address tools will ensure only accurate addresses enter your database.

A series of five-digit business postcodes may also be used on business mail. This is called Mailsort. Discounts are available for such bulk mailings based on the type of mail and how pre-sorted it is.


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