Britain’s biggest mobile phone network providers are facing a class action claim that their loyalty customers are being overcharged.

According to consumer rights champion and former Citizen’s Advice executive, Justin Gutmann, Vodafone, EE, O2 and Three are “abusing their dominant positions” in the UK mobile industry by charging a ‘loyalty penalty,’ in which long-standing customers were overcharged for handsets beyond the end of their contractual term.

Gutmann alleged the mobile operators have overcharged on up to 28.2 million contracts and, as a result, is seeking damages of at least £3.285 billion.

If successful, someone who held a contract with just one of the mobile operators could receive as much as £1,823.

Gutmann said: “I’m launching this class action because I believe these four mobile phone companies have systematically exploited millions of loyal customers across the UK through loyalty penalties – taking over £3 billion out of the pockets of hard-working people and their families.

“These companies kept taking advantage of customers despite the financial crisis of 2008, Covid and now the cost of living crisis. It’s time they were held to account.”

He added: “If our claim is successful, it will finally stop these firms from taking advantage of their loyal customers and stop the immoral practice of loyalty penalties.”