We take a look at the deals on offer from both providers to see what's on offer, and explain more about what you can expect.
The "ethical" mobile network could be just days from collapse, affecting thousands of customers. Which? explains what affected customers can do to get the best deal possible.
O2 and Three customers will see their mobile phone bill go up by 2.5% whereas EE customers will see their bills increase by 2.7%. Vodafone has also announced it will raise their prices but will confirm how much on Wednesday 20th March.
New analysis by Citizens Advice shows that over seven in ten mobile customers with a Sim-only plan are overpaying for data they do not use, affecting 12 million customers in the UK.
What are the roaming charges outside the EU? We researched 15 UK mobile providers to find the cheapest one 12 of the most popular holiday destinations.