Interesting facts and information about postcodes
Updated 20 Oct 2020
The biggest postcode area is IV, also known as Inverness. It is made up of 52 postcode districts for post towns.
There are 124 postcode areas in the United Kingdom. The average size of an area is 776 square miles and the average population is 533,000.
The UK postcode consists of five to seven alphanumeric characters which define four different levels of geographic unit. CH5 3QW has the longest addresses in terms of numbers of elements.
Each postcode area is divided into a number of districts which are represented by the numerical portion of each part of the postcode. These numbers range from 0 to 99.
Perhaps. Large user organisations have a postcodes entirely to themselves, however it's unlikely your letter will reach the intended recipient when it arrives at the destination.
Including the postcode in a letter is essential to ensure it is delivered to the correct address. A full address should include a premise identifier and post town at the very least.
Read our good addressing guide to ensure your mail is correctly addressed.
Postcodes are updated daily and available on Royal Mail’s Postcode Address File.
Royal Mail does not make changes to postcodes unless it is absolutely necessary and there is an operational reason. Residents can request changes; however, there has to be enough evidence that all the affected are in favour.
You can find out more in Royal Mail’s Code of Practice.
There are roughly 1.7 million postcodes in the UK.
Each postcode covers an average of about 15 properties. However, this is not a definitive number, where postcodes can hold up to 100.