Online safety organisation Internet Matters is set to lose about 15 per cent of its income as one of its co-founders is expected to withdraw support worth about £300,000 a year.
Internet Matters, which offers online safety advice to parents, carers and schools, was co-founded in 2014 by the telecommunications companies BT, Sky, TalkTalk and Virgin Media.
These businesses are understood to pay an annual membership fee of about £300,000.
But TalkTalk is set to stop providing its donation at the end of March, amid reports of a £120m cost-cutting plan.
Internet Matters recorded income of £1.9m in the year to the end of March last year, latest accounts show.
Asked what the loss of £300,000 a year in funding would mean for the charity, Carolyn Bunting, co-chief executive of Internet Matters, said in a statement the organisation would continue working with its partners to provide online safety advice.
“We would like to thank TalkTalk for the significant contribution it has made to Internet Matters for the past 11 years. Its support has been invaluable,” she said.
“Internet Matters remains committed to its mission to keep children safe online and is supported by a broad base of members and partners across a range of industries, and we look forward to continuing to work with them to provide families across the UK with the vital help that they need.”
A TalkTalk spokesperson told The Telegraph newspaper the company was proud to have financially supported Internet Matters for the past decade.
“We remain committed to online safety and are exploring different ways of continuing to support Internet Matters and its work moving forward,” the spokesperson said.