CM1 DISTRICT · CHELMSFORD
Writtle mobile coverage Three 100% indoors here, 83% across Chelmsford CM1 · Chelmsford
No network wins CM1 on overall coverage: all four score 100/100.
CM1: Writtle, Broomfield, High Easter, West Hanningfield, Chelmer, Roxwell, Chignall, Highwood.
CM1 scores
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EE
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O2
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Three
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Vodafone
Ofcom Mobile Coverage data (May 2025), measured across 96 addresses in 6 sampled postcodes: CM1 1RT, CM1 2BG, CM1 2DG, CM1 2GF, CM1 4HY, CM1 4JW. Methodology.
How CM1 compares
Against the Chelmsford average
- Three indoors: 100% here, 83% across Chelmsford (+17).
Weakest spot in Chelmsford: CM9 Maldon, where Three reaches 50% indoors.
Indoor signal around CM1
| District | km away | EE | O2 | Three | Vodafone |
|---|---|---|---|---|---|
| CM1 Writtle (here) | – | 100% | 100% | 100% | 100% |
| CM2 Great Baddow, Sandon | 4 | 100% | 100% | 100% | 100% |
| CM3 Hanningfield, Sandon | 9 | 100% | 96% | 100% | 63% |
| CM4 Billericay, Margaretting | 9 | 100% | 100% | 100% | 100% |
| CM8 Witham, Cressing | 14 | 100% | 100% | 100% | 100% |
| Chelmsford average | – | 97% | 98% | 83% | 93% |
Biggest difference nearby: Vodafone indoors, 100% here and 63% in CM3 Hanningfield, 9 km away.
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1pMobile runs on EE's network: £5 a month for 5GB (read 19 October 2026). A price, not a coverage ranking: Ofcom separates no network here.
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