London listing planned for 118 118 group

The company behind The Number, the directory enquiries business famed for its 1970s-style joggers sporting 118 118 running vests, is planning a £700m flotation. Infonxx, which has a substantial operation in the US, is considering listing on the London Stock Exchange.

Chris Moss, chief executive of The Number, said: "You have to build a solid business and show sensible returns, but I think the window will be in 18 months. It will be dependent on continued results, not just here but also in the US, where we have been growing quite rapidly. We are answering more than 1.5 million calls a day across America. The growth forecasts over the next year or two are pretty sizeable."

Since the UK deregulation of directory enquiries in August, The Number has established itself as the main competitor to BT, despite there being no less than 30 different 118 numbers. Mr Moss claimed The Number had overtaken BT's 118 500 service in terms of market share and had made an operating profit last month. "It was not huge. We will continue to invest in this business in the next two or three years," said Mr Moss. "We have already invested close to £60m."

One operator, Thus, has pulled out of the directory enquiries market. Another, Conduit, is effectively for sale. But Mr Moss denied speculation that The Number was a potential buyer. "It is not something we have talked about," he said, adding that The Number had been approached by other "well-known" directory enquiries companies looking to sell out.