Marshalswick mobile coverage Within 8 points of the St Albans average AL4 · Hertsmere
No network wins AL4 on overall coverage: all four score 100/100.
AL4: Marshalswick, Kimpton, Sandridge, Colney Heath, London Colney, Wheathampstead, Ridge, Hatfield (Hertsmere, North Hertfordshire, St Albans).
AL4 scores
Ofcom Mobile Coverage data (May 2025), measured across 162 addresses in 6 sampled postcodes: AL4 9AH, AL4 9EF, AL4 9HT, AL4 9PL, AL4 9SS, AL4 9TT. Methodology.
How AL4 compares
Every network here is within 8 points of the St Albans average and of AL1 Sopwell, AL10 Hatfield, AL3 Harpenden and AL5 Harpenden, indoors and outdoors.
Weakest spot in St Albans: AL2 Shenley, where Vodafone reaches 71% indoors.
Indoor signal around AL4
| District | km away | EE | O2 | Three | Vodafone |
|---|---|---|---|---|---|
| AL4 Marshalswick (here) | – | 100% | 100% | 100% | 100% |
| AL1 Sopwell, Verulam | 3 | 100% | 100% | 100% | 100% |
| AL10 Hatfield, North Mymms | 5 | 100% | 100% | 100% | 100% |
| AL3 Harpenden, Redbourn small sample | 6 | 92% | 83% | 92% | 92% |
| AL5 Harpenden, Wheathampstead | 6 | 97% | 100% | 100% | 100% |
| St Albans average | – | 99% | 100% | 98% | 98% |
Small sample: under 30 addresses sampled.
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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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