Broadband availability
Broadband in Castlerock
Showing results for postcode BT51 3NT.
Compare Broadband Deals in Castlerock
Broadband Types Available in Castlerock
| 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 Castlerock
Full fibre (FTTP) is available in Castlerock, with typical download speeds of around 858 Mbps. This is the fastest and most reliable type of home broadband connection.
Broadband Providers in Castlerock
Customer ratings sourced from Trustpilot. Checked 18 June 2026.
Postcodes in Castlerock
Nearby Areas
About Broadband in Castlerock
Castlerock is in Causeway Coast and Glens. Full fibre broadband is available here, with typical download speeds of around 858 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 Castlerock?
Castlerock is in a strong position for broadband in 2026. The village sits within the Causeway Coast and Glens area of Northern Ireland, where Fibrus has been one of the most active full fibre (FTTP) builders in the UK. By May 2026, Fibrus had passed more than 150,000 premises across Northern Ireland with its gigabit-capable network, and Castlerock falls within its coverage footprint. Openreach is also active in the area, giving residents more than one provider to choose from for full fibre connections.
Properties here can access speeds of around 858 Mbps on a full fibre connection, well above the UK national average download speed. Nationally, around 82% of homes can receive FTTP and 89% have access to gigabit-capable broadband as of Spring 2026. Northern Ireland has been one of the better-served regions for full fibre rollout, partly due to targeted investment through the UK Shared Rural Network and altnet expansion by Fibrus.
No specific rollout announcements for Castlerock were found in trade press at the time of writing. If you are on an older copper or part-fibre connection, it is worth checking availability now. BT's PSTN copper network is being switched off in January 2027, meaning any remaining copper-only lines will need to migrate to a digital service before then. Residents on older phone and broadband packages should contact their provider to confirm they are ready.
To see which full fibre and gigabit packages are available at your specific address in Castlerock, use the postcode checker at the top of this page.