I have seen people here in the past recommend Vodafone for rural areas, however it seems they are the worst for rural coverage, even for a basic phone service.

http://www.theguardian.com/money/201...services-ofcom

Quote:
“Ofcom used independent firm RootMetrics to analyse call data, and found that typically only around of 85% of calls made in rural areas pass off without a problem.

It found that just 79.9% of Vodafone 2G and 3G calls in rural areas completed successfully, compared to 86% over the 3 network, 87.4% on O2 and 93.7% on EE. In urban areas, EE was again top, successfully completing 97.5% of calls, with Vodafone again bottom at 95.3%.

The figures include "blocked" calls, when a user has a signal but can't make a call due to lack of capacity, and "dropped" calls, when a call is connected but terminates unexpectedly. The issue is not just frustrating for users but also costly, as they have to call two or three times to complete a conversation.

In June, David Cameron – a Vodafone customer – ordered ministers to improve mobile phone coverage across the countryside after becoming frustrated at the lack of mobile reception”