Postcode unit
A postcode unit is a full UK postcode, such as N7 6PA. It covers about 15 addresses on average, often part of a single street.
A postcode unit is a complete postcode, both halves together. N7 6PA is a postcode unit. It is the smallest level of the postcode system and the one written on every address.
There are about 1.8 million live postcode units in the UK. A unit covers an average of around 15 addresses, and no more than 100, so it is usually part of a street rather than the whole of one.
How a unit is built
A postcode has two halves. The first half is the postcode district, such as N7. The second half is always one number and two letters, such as 6PA. The number gives the postcode sector and the two letters narrow it down to the unit.
A long road can have several units along its length, often one for each side or each stretch of house numbers. A small cul de sac may share a unit with the road next to it.
Large user postcodes
Most units are shared by a group of homes. Some are given to a single address that receives a large amount of mail, such as a business or a public body. These are known as large user postcodes. They rarely appear in house sale records, because most are offices rather than homes.
Units in sold price records
Every sale in HM Land Registry's Price Paid Data carries the full postcode of the property. The postcode is the one in use at the time of the sale. If Royal Mail later changes it, the old record is not updated.
A unit has too few sales for a typical price on its own. Many units see no sale at all in a given year, and one sale can be a very different home from the next. That is why sold prices are usually grouped by street, sector or district. Our guide on how to find what a house sold for shows how to look up sales at a single postcode or address.
Postcodes change
Units are not fixed. Royal Mail creates new ones for new developments and can retire or move old ones. A postcode that is no longer used can later be given to a different place. When you look back at older sales, check that the postcode still points to the street you have in mind.
| Example | N7 6PA |
| Second half | One number and two letters |
| Average addresses | Around 15 |
| Maximum addresses | 100 |
| Live units in the UK | About 1.8 million |
Related terms
Postcode sector · Postcode district · Postcode area · Price Paid Data · Comparables