Stour Valley mobile coverage O2 66% indoors here, 90% across Colchester CO9 · Braintree
Three has the best measured coverage in CO9: 98/100, 6 points ahead of Vodafone on Ofcom's overall score, with EE within 2 points.
CO9: Stour Valley, Gosfield, Coggeshall, Greenstead Green, Halstead, Pebmarsh, Birdbrook, Ridgewell (Braintree).
CO9 scores
Ofcom Mobile Coverage data (May 2025), measured across 70 addresses in 5 sampled postcodes: CO9 1UH, CO9 2RJ, CO9 3JN, CO9 3NP, CO9 3QT. Methodology.
How CO9 compares
Against the Colchester average
- O2 indoors: 66% here, 90% across Colchester (−24).
- Vodafone indoors: 66% here, 86% across Colchester (−20).
Weakest spot in Colchester: CO6 Marks Tey, where Vodafone reaches 21% indoors.
Lowest indoor figure of the 8 Colchester districts sampled, for O2.
Indoor signal around CO9
| District | km away | EE | O2 | Three | Vodafone |
|---|---|---|---|---|---|
| CO9 Stour Valley (here) | – | 93% | 66% | 90% | 66% |
| CO8 Assington, Lamarsh | 11 | 100% | 75% | 100% | 65% |
| CO6 Marks Tey, Coggeshall | 13 | 51% | 95% | 90% | 21% |
| CO3 Stanway, Birch | 19 | 100% | 77% | 100% | 100% |
| CO1 Tiptree, Myland | 22 | 100% | 100% | 100% | 100% |
| Colchester average | – | 90% | 90% | 91% | 86% |
Biggest difference nearby: Three indoors, 90% here and 100% in CO8 Assington, 11 km away.
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iD Mobile runs on Three's network: £6 a month for 15GB (read 19 October 2026). A price, not a coverage ranking: Three leads this page on Ofcom's data alone.
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