BT is to launch a detailed study of its 66,000 payphones as it seeks to put pressure on the telephones regulator to rethink rules that force it to fund and maintain the boxes.

The telecoms group is seeking to provide proof to Ofcom that, in an age of mobile phones and other new technologies, payphones no longer play the vital social role that they once did. The study will provide up-to-date information about who uses the phones, in which parts of the country they are most used and what - if any – social benefit they provide.

BT, which says that it can no longer absorb the costs of so many unprofitable boxes, will seek to show, for example, how many emergency calls made from its phones are genuine - and are not merely nuisance calls made by children. The report, which will not be made public, will be handed to the regulator to try to encourage it to rethink BT’s role in supporting call boxes around Britain even where it does not make money out of them.

The study could prompt the regulator to review the issue, which is not formally due for examination for at least two years.

BT has been responsible for providing and maintaining public call boxes, even where they are unprofitable, since its 1984 privatisation. The commitment is one of several universal service obligations (USOs) aimed at ensuring that everyone has access to basic telephone services at an affordable price. However, the boom in mobile phones, BT says, has made pay phones less relevant to people today.

Virtually no adults use payphones as their main phone, the group’s most recent data shows, and takings from kiosks have plummeted. Nearly 12,000 of its call boxes, BT says, take less than £100 a year.

Meanwhile, it complains, it is left with sole responsibility for maintaining the 66,000 boxes – including repairs after vandalism – at an average cost of £1,409 per payphone per year. It “seems right”, the group argues, to remove public payphones from USO status.

Ofcom last reviewed the USO in 2006. It concluded that BT drew some benefits from areas with phoneboxes – boosting its image, for example - and that these benefits amounted to £64 million. There was, the regulator concluded, no “undue financial burden” on BT from the USO.

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