Mobile customers overpaying by £800m a year for data

New analysis by Citizens Advice shows that more than seven in ten mobile customers with a Sim-only plan are overpaying for data they do not use, affecting 12 million people in the UK.

This comes at a total cost of £800m per year, according to the analysis, with Sim-only customers facing potential savings of £63 per year if they switch to a better deal.

Find out which providers combine value with great customer service in our guide to thebest and worst mobile phone providers.

Who is affected and how?

Citizens Advice analysis showed that the average amount of data being wasted per customer was 2GB, which is equivalent tostreaming three hours of video or 28 hours of music. This jumps up to 4.2GB for people who bought their phone in a store, suggesting that sales practices in-store could be pushing consumers to take out packages that have far more data than they need.

For those customers who bought online, the average data wastage was 2.6GB.

While polling only asked Sim-only customers their data usage, Citizens Advice said this likely affects people who have bundled contracts, too. This would mean that the £800m a year figure would likely be much higher if people on a mobile phone contract were to be added.

Gillian Guy, Chief Executive of Citizens Advice, said:

Previous research by Citizens Adviceshowed that an estimated four million people who had a mobile phone contract were beingcharged the same price after paying the phone off, costing them a total of £490m extra on their contracts.

Cheapest Sim-only deals

If you feel you're not getting good value for your data, or overpaying on your monthly allowance, our table below shows some of the best low to medium data deals you can get right now.

If you're not looking to switch, an alternative might be to get more from your current supplier. Our guide on how to haggle with your mobile providercan help you save money on your existing mobile plan.

Three ways to manage your data more effectively

If you're thinking of switching to a deal with less data but are concerned that you might go over your data allowance, here are three ways you can help to keep things under control.

Master your usage

If you don't know already, find out how much data you actually use each month. Check previous bills from your provider, or contact them for a summary of usage. Our guide onhow to check your mobile data and minutes has plenty of help and advice on managing your usage.

Stick to wi-fi

This may seem obvious - but it can be easy to forget you're using data when wi-fi is readily available. It's usually best to leave wi-fi turned on all the time, so that you automatically connect to known networks when you get back home, reach the office or another location with a hotspot. If you're struggling to get a consistent connection in the home, read our guide to extending your wi-fi.

Download your content

Download content to your phone through wi-fi. Getting into the habit of doing this can save data and ensure you get an uninterrupted experience. Download music you listen to often on Spotify, TV shows to watch on the move or even webpages you want to read later. Read our guide on how to prepare your mobile phone for holidaysfor tips and apps on ways you can save data.