What area is the CO4 postcode in?

CO4 is a postcode district in Colchester, Colchester, East of England, England. It is part of the CO postcode area.

How many addresses are in the CO4 postcode?

The CO4 postcode district covers Colchester in Colchester. The exact address count can be retrieved via the APITier Postcode Lookup API.

How do I look up addresses in CO4 programmatically?

Use the APITier Postcode Lookup API: GET https://postcode.apitier.com/v1/postcodes/{postcode}?x-api-key=YOUR_KEY — where the postcode begins with CO4. The response returns all PAF addresses as structured JSON including building name, number, street, town, county, and geocoordinates.

Royal Mail PAF · East of England

CO4 Postcode — Colchester

CO4 is a postcode district in Colchester, Colchester, East of England, England. Use the lookup below to explore addresses within this postcode district.

CO4

Postcode District

CO — Colchester

Area

East of England

Region

Royal Mail PAF

Data Source

Postcode Lookup — CO4 DistrictSample

{
  "_note": "Sample response — enter any postcode above and click Lookup for live data",
  "status": 200,
  "result": {
    "postcode": "CO4 1AA",
    "quality": 1,
    "eastings": 606360,
    "northings": 267815,
    "country": "England",
    "nhs_ha": "East of England",
    "longitude": 0.948,
    "latitude": 51.8632,
    "european_electoral_region": "East of England",
    "primary_care_trust": "Colchester",
    "region": "East of England",
    "lsoa": "Colchester 001A",
    "msoa": "Colchester 001",
    "incode": "1AA",
    "outcode": "CO4",
    "parliamentary_constituency": "Colchester",
    "admin_district": "Colchester",
    "parish": "Colchester, unparished area",
    "admin_county": "East of England",
    "admin_ward": "Colchester Central",
    "ced": null,
    "ccg": "NHS East of England",
    "nuts": "Colchester",
    "codes": {
      "admin_district": "E07000000",
      "admin_county": "E10000000",
      "admin_ward": "E05000000",
      "parish": "E43000000",
      "parliamentary_constituency": "E14000000",
      "ccg": "E38000000",
      "lsoa": "E01000000",
      "msoa": "E02000000"
    }
  }
}

About the CO4 Postcode District

The CO4 postcode district is part of the Colchester (CO) postcode area, covering Colchester and surrounding areas in East of England, England.

Postcodes in the CO4 district follow the format CO4 nXX where n is a digit and XX are letters. Each inward code identifies a specific delivery walk within the district.

The wider Colchester postcode area (CO) also covers: Clacton-on-Sea, Harwich, Mersea Island, Halstead.

Frequently Asked Questions

What area does the CO4 postcode cover?

The CO4 postcode district covers Colchester in Colchester, East of England, England. It is one of 14 districts in the CO postcode area.

How do I look up all addresses in the CO4 postcode?

Use the live lookup widget above or call the APITier Postcode Lookup API: GET https://postcode.apitier.com/v1/postcodes/{full postcode}?x-api-key=YOUR_KEY. Replace {full postcode} with any complete postcode beginning CO4. The API returns all Royal Mail PAF addresses as structured JSON.

Is CO4 a valid UK postcode district?

Yes. CO4 is a Royal Mail postcode district in Colchester, England. Full UK postcodes in this district follow the format CO4 followed by a digit and two letters (e.g. CO4 1AA).

CO4 Postcode — Colchester

About the CO4 Postcode District

Frequently Asked Questions

Other Colchester Postcode Districts