CO3 postcode district: Colchester and around, Essex

CO3 is a postcode district in Essex, with 864 postcodes in use in 5 sectors. It has postcodes in Colchester. Its council is Colchester.

Postcodes in use: 864
Sectors: 5
Council: Colchester
Places: Colchester

Source: Office for National Statistics (ONS) Postcode Directory, August 2026, loaded 20 October 2026. See all our data sources

Every postcode in CO3, and which are new since 2020

New since 2020: 33
In use before 2020: 831
Outline: where 5 or more new postcodes since 2020 lie together

Of the 864 postcodes in CO3 that ONS places, 33 are new since 2020 and 831 were in use before 2020.

Each mark is a postcode's centre point as ONS gives it, not a building. Press one to see its postcode and open its page. New since 2020 means it came into use in January 2020 or later. A dashed outline shows where 5 or more lie within 150 metres of each other. It is not a boundary, and no boundary is drawn. Where marks overlap, the one first in the key is drawn; the counts include every postcode.

The middle of its postcodes: latitude 51.8847, longitude 0.8555. Open this area on OpenStreetMap

Source: Office for National Statistics (ONS) Postcode Directory, August 2026, loaded 20 October 2026, the centre point of each postcode; when each came into use: the same directory; roads, rivers and built-up areas: Contains OS data © Crown copyright and database right 2026. Drawn by us. Street map: Ordnance Survey, OS Open Zoomstack, Open Government Licence v3.0, drawn with MapLibre. How we use them

The 5 newest postcodes

CO3 8DYMarch 2026 CO3 9FXSeptember 2024 CO3 8PFMarch 2024 CO3 8PEDecember 2023 CO3 9FWNovember 2023

Where the new postcodes lie together

6 new postcodes since 2020, outlined on the map. CO3 9FX, is the newest of them.
5 new postcodes since 2020, outlined on the map. CO3 9FS, is the newest of them.

What broadband can you get in CO3?

Ofcom reports on 855 of the 864 postcodes in CO3. At 673 of them every home and business can get gigabit broadband.

Postcodes where every home can get gigabit673 of 855

Postcodes where every home can get superfast812 of 855

Ofcom gives each postcode's share of homes and businesses, not how many there are, so these count postcodes. Each postcode page has its own figures. A provider's checker answers for one address.

Check one address on Ofcom's checker

Source: Ofcom, Connected Nations, Spring 2026, data for January 2026, Open Government Licence v3.0. How we use it

Is CO3 at risk of flooding?

17 of the 864 postcodes in CO3 have a home or business in an area at risk of flooding from rivers or the sea, the Environment Agency says. At those, it puts 48 homes and businesses in an area at high or medium risk.

Homes and businesses in an area at risk, at 17 of 864 postcodes High: 13Medium: 35Low: 106Very low: 1

High: 3.3% or more a year (1 in 30). Medium: 1% to 3.3% a year. Low: 0.1% to 1% a year. Very low: under 0.1% a year (1 in 1,000). Each band is the chance of flooding in any one year.

Homes and businesses in an area at risk of flooding from rivers or the sea, as the Environment Agency counts them, added up over the postcodes. It is for the land, not each building, and leaves out surface water, groundwater and sewers. Each postcode page has its own figures and its flood warning areas.

Source: Environment Agency, Risk of Flooding from Rivers and Sea (postcodes in areas at risk), published 6 July 2026, Open Government Licence v3.0. How we use it

What do homes sell for in CO3?

Homes in CO3 sold for a typical £350,000 in the 12 months to August 2026, across 429 sales, down 1.4% on the 12 months before, HM Land Registry's figures show.

£350,000 typical price, the 12 months to August 2026

£355,000 12 months to August 2025

▼ down 1.4% on the 12 months before

Detached £450,000 160 sales
Semi-detached £335,000 136 sales
Terraced £290,000 62 sales
Flat or maisonette £175,000 71 sales

Each bar is that kind's typical price, against the most expensive kind here.

Standard sales of homes at market value. A typical price is the median, the middle sale. Sales take weeks to be registered, so the last month or two are incomplete. Each postcode page gives the figure for its own postcode sector.

Source: HM Land Registry Price Paid Data, files dated 28 September 2026. Contains HM Land Registry data © Crown copyright and database right 2021. This data is licensed under the Open Government Licence v3.0. How we use it