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Coverage & signal guidance
Three: checking coverage and improving signal
Practical, general steps for checking whether Three works well at your address and what to try when signal is poor.
Independence notice
Thirdgreenovo is an independent third-party information service. We are not affiliated with, authorised by, or acting for any network named on this page. Trade marks belong to their owners and identify the subject of guidance only. For account, billing or contract matters, contact your network's official customer service. Calls to our line are standard geographic rate and provide general guidance only.
Checking Three coverage the right way
- Use the official Three coverage checker with your full postcode, and note the difference between outdoor and indoor predictions.
- Cross-check with Ofcom's coverage checker, which applies the same standard to all networks and is independent of any operator's marketing.
- Test in person if possible. A 30-day or pay-as-you-go SIM is a low-cost way to test real performance at home, at work and on your commute before committing.
Improving a weak Three signal
- Wi-Fi Calling: switch it on in your phone settings — the single most effective fix for indoor dead spots.
- 4G Calling (VoLTE): ensure it is enabled so calls can use the 4G layer rather than falling back to older technology.
- Airplane-mode reset: toggling airplane mode for ten seconds forces the phone to re-register with the nearest mast.
- Software updates: carrier settings updates frequently include network fixes.
- Building materials: foil-backed insulation and low-E glass block signal; a window position can improve reception noticeably.
4G vs 5G on Three
Three's 5G is fast where present, but 5G coverage is still concentrated in towns and cities. If the coverage checker shows 4G only at your address, judge the network on its 4G performance — that is what you will use most.
Persistent faultsIf coverage that was promised at signup materially fails, keep dated records and raise a formal complaint — see our complaints and rights guide for the 8-week and ombudsman process.