Start with the places you use your phone, not a national coverage headline. A plan with more data will not solve a weak signal in your kitchen or at work.
Check more than one postcode
Use Ofcom’s Map Your Mobile to compare coverage and local performance. Check your home, workplace and places you visit often. The tool combines predicted coverage with information about people’s real experience.
A map is a useful starting point, not a promise for every room. Buildings, the phone itself and local conditions can affect reception. Look at the provider’s own coverage checker too.
Find out which network the provider uses
The name on a SIM plan may differ from the network carrying its signal. Look for the provider’s current network information before comparing maps. Sharing a network does not mean two plans include the same speeds, Wi-Fi calling, roaming or support.
Test the things you actually do
- Calls: try the rooms and places where you normally make them.
- Data: check maps, messages and the apps you need at busy times as well as quiet ones.
- Travel: consider your commute and regular trips, not just your home address.
- Wi-Fi calling: ask whether your exact phone and plan support it. Do not assume it comes with every SIM.
If you are unsure, a short plan may make it easier to try a provider. Read its payment, cancellation and return terms first; a short minimum term is not a free trial.
Make a small shortlist
Once you have two providers that look suitable, compare the allowance, billing period and term. Our side-by-side SIM comparison keeps those details together. Check the latest coverage with the provider before you join.
Reviewed 29 October 2026 · Here4Mobiles