According to the latest Which? survey, over 10 million British users overpay for their mobile phones.
It claims that British users are paying extra for extra texts, call-time and data over and above their monthly line rental with their network provider.
Which? claims that the findings were "not surprising" as over 6 million users had no idea of their monthly limit for call minutes, while 5 million were unsure of their text and data allowances that the contracts gave them.
Consumers seem to be shy of scouting around to find a suitable tariff for their needs, as the survey shows that over 18 million users had never switched mobile phone providers.
Tom McLennan, head of Which? Mobile, said, "You could be spending hundreds of pounds more than you need to on your mobile every year if you're not on the right tariff."
He also suggested that if users spend more than their line rental, they should find out from their bills where they're incurring extra charges and save money by moving to another plan with more minutes, text or data, depending on one's needs.
The opposite also held true. He said, "If you never go over your agreed line rental, it's because you're not using up your allowance so you may be able to save money by finding a cheaper tariff that reflects your usage."
The survey by Which? spanned a group of 1,271 adults, aged 16 years or more.
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