CO4 postcode district: Colchester and around, Essex

What broadband can you get in CO4?

Ofcom reports on 1,177 of the 1,193 postcodes in CO4. At 922 of them every home and business can get gigabit broadband, and at 8 some cannot get decent broadband (10 Mbit/s).

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.

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

Is CO4 at risk of flooding?

27 of the 1,193 postcodes in CO4 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 436 homes and businesses in an area at high or medium risk.

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 CO4?

Homes in CO4 sold for a typical £325,000 in the 12 months to August 2026, across 535 sales, up 1.6% on the 12 months before, HM Land Registry's figures show.

• Detached £422,500 174 sales
• Semi-detached £320,000 167 sales
• Terraced £280,000 118 sales
• Flat or maisonette £173,000 76 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

Places in CO4

Towns and villages with postcodes in CO4, and how many each has here.

Who covers CO4

How many of the district's postcodes in use fall under each council, constituency and police force area.