Field note · United Kingdom
Mobile Phone Signal Booster Guide
How signal boosters work, what coverage you can expect, and how to choose the right kit.
Short answer
Start by testing service outside and checking the options for your address.
Compare at the same place
Test EE, O2, Vodafone and Three at the same outdoor points and at the same times if possible. Record whether calls connect, whether they stay connected, and whether data loads. Repeat the test in the rooms where you need coverage. The result can change from one side of a building to another.
Check the exact provider behind your SIM if you use a smaller brand. Then ask the provider which frequencies are relevant at your postcode and confirm them against the handset diagnostics. Do not assume that a product advertised for one brand works with every brand or with every service on a shared or changing network.
If an active repeater is under consideration, use Ofcom's published guidance and request evidence for the exact model.
For an operator-specific starting point, see the existing EE, O2 and Vodafone guides, then compare with Ofcom's current information.
Frequently asked questions
Which UK network has the best indoor signal?
It depends on the address, building and device. Compare networks at the property rather than relying on a national ranking.
Will one repeater work with EE, O2, Vodafone and Three?
Not automatically. Verify the exact model's bands, services and applicable Ofcom evidence for the networks you use.
Does an MVNO use the same network as its host?
Some smaller providers use another operator's network, but check the current arrangement with the provider rather than assuming.
Should I choose from another postcode's experience?
No. Nearby streets and different buildings can have different service. Test at your own property.
What should I record during a comparison?
Note address, room, time, handset, SIM provider, call behaviour, data behaviour and any displayed network-frequency details.