The majority (71%) of mobile customers with a SIM-only plan are overpaying for data they don’t use, at a total cost of £800 million per year, according to new analysis from Citizens Advice. overpaying for data

The average amount of data wasted each month was 2GB. This is equivalent to streaming 3 hours of video or 28 hours of music.

Citizens Advice estimates this affects 12 million people in the UK who have a SIM-only contract. While polling only asked SIM-only clients, Citizens Advice said this likely affects people who have bundled contracts too.

People who purchased their contract in store were found to waste 4.2GB on average, while those who bought online waste 2.6GB, suggesting sales practices in store could particularly be leading consumers to take out contracts with excessive data allowances.

The charity is urging more mobile networks to refund unused data, or make it easier for customers to reduce their monthly allowance if they find they are wasting data repeatedly.

This is another example of mobile companies overcharging customers that Citizens Advice has revealed.

The charity previously found mobile phone companies profit £475 million each year by continuing to charge customers for phones they have already paid off. Broadband companies earn £1.2bn annually from the loyalty penalty, by charging loyal customers more for their services.

Citizens Advice is calling for an independent consumer champion for the mobile and broadband industries to stand up to practices that exploit customers.

Gillian Guy, Chief Executive of Citizens Advice, said: “Mobile companies should be doing more to help their customers save on data they don’t use, especially when it’s clear people are consistently underusing their allowance.

“This is another example of mobile companies overcharging their customers. It’s time for a consumer champion to stand up for people and push for change on issues like this.

“While we wait for industry to improve support for customers, individuals can take action too. Anyone looking to save money should check their data usage and see if they can switch to a cheaper deal that matches what they use.” overpaying for data