British mobile phone users who switched operators during the last year have collectively cut their yearly bills by £1 billion, according to uSwitch.
The price comparison and switching service noted that the 17 million mobile users who have never switched networks could make savings of £1.9 million annually by changing providers.
Not wanting to lose their existing number is the main reason why people stick to one operator, according to uSwitch, with more than 12 million admitting they would switch more frequently if the process were easier.
It is possible for mobile customers to keep one number when switching operators, but the process takes five days in the UK. According to uSwitch, this is 350 times longer than in Ireland.
Steve Weller, head of communications services at uSwitch, said the UK's number porting process is "archaic".
Ofcom should speed up its process of bringing the UK in line with the rest of Europe, he said.
In July, the regulator announced a consultation aimed at improving the process of transferring mobile numbers to new suppliers.
But while the process is slow, consumers could still be saving money through switching operators.
"In the meantime, while the number porting process is not perfect, it does exist, and the saving of £113 is well worth the effort," Mr Weller added.
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