BT has become the first mobile operator in the UK to make calls to 0800 and similar 0500 numbers free for its mobile customers. The change will take effect on 1 May.
Although 0800 numbers are usually free from landline phones, some mobile carriers charge up to 25p per minute for these calls, which BT estimates racks up around £50m a year in extra charges.
The move has garnered praise from campaign group Consumer Focus, which has called on other mobile operators to follow BT's lead.
"Scrapping unfair charges on 0800 calls from mobile phones is good news for BT customers," said Consumer Focus' Audrey Gallagher.
"With so many consumers using mobile phones rather than landlines to contact essential services, find information and seek help, it is more important than ever that they do so for free across all 0800 numbers."
The move follows BT's recent announcement that all landline calls to 0870 and 0845 numbers would be free to its customers.
"We think that mobile customers are irritated by having to pay high rates to call 'free' 0800 numbers, so we have put our own house in order by making it free for any BT Mobile customer to call these numbers," said John Petter, managing director of BT's consumer business.
"We have all called an 0800 number from our mobiles and experienced the frustration of the message telling us that the call will be charged at standard rates.
"We had already made calls into BT free for our 14 million landline customers, and we are happy to back Consumer Focus and other consumer organisations in their efforts to address this anomaly."
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