CO3 postcode district

Postcodes and sectors

864 of the district's 1,458 postcodes are live in the ONS Postcode Directory of August 2026. A postcode directory says whether a code is in use, never who is there. The live postcodes centre on 51.88468, 0.85551, which locates the district, not a building.

Companies registered in CO3

Companies House lists 3,088 companies with a registered office in CO3; 960 of them at addresses shared by 25 or more companies (1 October 2026 snapshot). 25 is the count at which the address lookup reports a company cluster.

Places OS Open Names lists for CO3

• Colchester
• Essex
• Eastern
• Eight Ash Green
• Copford
• Heckfordbridge

Roads filed under CO3

Named roads first, then numbered ones. A road is filed under one district even where it runs through several, so a street missing here may be listed under a neighbouring district — which is why the address lookup never calls a British street absent. Great Britain has no open register of buildings, so a listed road never means a building on it exists.

• Aardvark Drive
• Acland Avenue
• Alan Way
• Albertine Close
• Alexandra Road
• Alexandra Terrace
• Allen Aldridge Grove
• Alley Pond Close
• All Saints Avenue
• Alton Drive
• Ambrose Avenue
• Argents Lane
• Ashley Gardens
• Ash Way
• Athelstan Road
• Audley Road
• Back Lane
• Baden Powell Drive
• Bailey Dale
• Baines Close
• Bale Close
• Balkerne Hill
• Barley Way
• Barn Fields
• Batterham Close
• Bawtree Way
• Beaconsfield Avenue
• Beacon Way
• Beaver Close
• Becker Road
• Beech Grove
• Beech Hill
• Betony Way
• Beverley Road
• Birch Park
• Blackberry Road
• Blackbird Close
• Bluebottle Grove
• Bramley Close
• Brian Cadman Gardens
• Brick Street
• Bridlewalk
• Brimstone Chase
• Brood Chase
• Brougham Glades
• Browning Close
• Brownsea Way
• Bryanstone Mews
• Burlington Road
• Burns Avenue
• Burton Way
• Butterfly Trail
• Butt Road
• Byron Avenue
• Cadenhouse Mews
• Cambridge Road
• Cambridge Walk
• Cape Close
• Capel Road
• Carshalton End

Check an address in CO3

Check an address in CO3

The same road list through the API, from the outward code alone:

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=CO3" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about CO3

What does a CO3 postcode tell you?

That the address lies in the CO3 district of the CO (Colchester) postcode area, and the place OS Open Names most often lists first for its postcodes is Colchester. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 864 live postcodes.

Where the counts come from

• ons-postcode-directory · version 2026-08 · Contains ONS, OS and Royal Mail data © Crown copyright and database right 2026, Open Government Licence v3.0. Northern Ireland postcodes are excluded: their reuse needs a Land & Property Services licence.
• os-open-names · version 2026-11-01 · Contains OS data © Crown copyright and database right 2026, Open Government Licence v3.0.
• uk-companies-house · version 2026-10-01 · Companies House free company data product, Open Government Licence v3.0

What each figure means, and what a district page never says, is set out in Reading a British postcode district page; the glossary defines a postcode district, a postcode area, a postcode directory and a street register.

Data synced on 2026-11-01: the newest version among the datasets listed above.

Districts nearest CO3

• CO12.9 km
• CO23.1 km
• CO45.1 km
• CO66.3 km
• CO58.1 km
• CO710.3 km
• CO811.6 km
• CO1116.5 km
• CM817.4 km
• CO919.3 km
• CM919.3 km
• CO1619.7 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids