Postcode sector
A postcode sector is a postcode district plus the first digit of the second half, such as N7 6. It sits between a district and a single postcode.
A postcode sector is the postcode district followed by the first digit of the second half of the postcode. In N7 6PA the sector is N7 6. It covers a smaller patch than the district, usually a group of neighbouring streets.
There are around 12,500 postcode sectors in the UK. Each postcode district is split into a handful of sectors, and each sector is split into many postcode units.
Where the sector sits in a postcode
The second half of a postcode is called the inward code. It is always three characters long: one number followed by two letters. The number picks out the sector within the district. The two letters then pick out the unit within the sector.
So N7 6PA and N7 6QB are in the same sector, N7 6, but N7 0HY is in a different one. A district might have sectors numbered 0 to 9, though most use only some of those numbers.
Using sectors for prices
A sector is a useful middle step between a whole district and a single street. It is local enough to separate one side of a district from the other, which matters where a district is very mixed.
The trade off is the number of sales. A sector may record only a few sales of each property type in a month, so a typical price for it moves around more than a district figure. Looking at a longer period, such as six months or a year, gives a steadier result.
Sectors are often used to find comparables: recent sales of similar homes close to the one being priced. A sale in the same sector is usually nearer, and more alike, than a sale from the other side of the district.
Things to bear in mind
Sector edges are drawn for delivering mail. They do not follow school catchments, council wards or the line between streets that feel different, and a long road can run through more than one sector.
Royal Mail adds and changes postcodes over time, for example when a new estate is built. Price Paid Data keeps the postcode used at the time of each sale, so older sales stay under the sector they were in then. Our guide to comparing streets and postcodes explains how the levels relate.
| Made up of | District plus first digit of the inward code |
| Example | N7 6 in N7 6PA |
| Number in the UK | Around 12,500 |
| Splits into | Postcode units |
Related terms
Postcode district · Postcode unit · Postcode area · Comparables · Median price