Broadband availability
Broadband in Castle Cary
Showing results for postcode BA21 5SW.
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Broadband Types Available in Castle Cary
| Type | Status | Download | Upload |
|---|---|---|---|
| Standard Broadband | Not available | — | — |
| Superfast Broadband | Available | 36 Mbps | 20 Mbps |
| Ultrafast / Full Fibre | Available | 900 Mbps | 900 Mbps |
| Mobile Broadband | Available | N/A | N/A |
Best option in Castle Cary
Full fibre (FTTP) is available in Castle Cary, with typical download speeds of around 885 Mbps. This is the fastest and most reliable type of home broadband connection.
Broadband Providers in Castle Cary
Customer ratings sourced from Trustpilot. Checked 18 June 2026.
Postcodes in Castle Cary
Nearby Areas
About Broadband in Castle Cary
Castle Cary is in Dorset. Full fibre broadband is available here, with typical download speeds of around 885 Mbps, well above the UK average of 69 Mbps. Most major providers cover the area, so there is a reasonable amount of competition on price.
Standard broadband runs over the copper phone network. Speeds depend on your distance from the telephone exchange and typically range from around 5 Mbps to 20 Mbps.
Superfast broadband (FTTC) uses a fibre optic cable to your street cabinet, then copper for the final stretch to your home. Most urban and suburban areas can get speeds of 35 to 80 Mbps.
Full fibre (FTTP) runs fibre optic cable all the way into your home. It is the fastest and most reliable option available, with speeds from 100 Mbps upwards.
What's Happening with Broadband in Castle Cary?
Castle Cary is well served by full fibre broadband. Openreach has built its Fibre-to-the-Premises (FTTP) network across the town, with speeds available up to around 885 Mbps on the right package. That puts Castle Cary comfortably ahead of the UK average: nationally, FTTP reaches roughly 82% of premises and gigabit-capable broadband around 89% of homes as of Spring 2026, according to Ofcom data. Residents here can access those speeds today, not wait for them.
No Castle Cary-specific rollout announcements were found at time of writing, so no local expansion news is included here. The broader South West picture is positive: BDUK (Building Digital UK) had delivered full fibre to 194,750 premises across the region by March 2026, making the South West one of the strongest performing areas nationally for publicly funded gigabit delivery.
Wessex Internet is worth knowing about if you live in the rural fringes around Castle Cary. The Somerset-based altnet holds a Project Gigabit contract covering Dorset and South Somerset (Lot 14, 21,400 premises, £33.5m in state aid) and is actively building FTTP across rural communities in Somerset, Dorset, Hampshire and Wiltshire. In an interview with ISPreview published in April 2026, CEO Hector Gibson Fleming confirmed the network had passed 50,000 premises with plans to reach 137,000. If you are in a hamlet or farm outside the town boundary, Wessex Internet may be your fastest route to full fibre before Openreach reaches you.
One change that will affect all Castle Cary residents regardless of provider: Openreach is closing the old analogue copper phone network (PSTN) in January 2027. If you still have a traditional landline phone, you will need to switch to a digital voice service before then. Most major ISPs will handle this migration automatically, but it is worth confirming with your provider now, particularly if you use a monitored alarm or telecare device that relies on the copper line.
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