Private equity groups are said to be circling Costa Coffee after parent company Whitbread announced it would be spun off from its hotel business, last month.
The coffee giant will become a separate entity to Whitbread's Premier Inn brand within two years, following demands from the company's largest investor, Elliott Advisors.
Reports published by iNews claim 2,400 branch Costa Coffee has been valued between £2b and £3b.
Those believed to have approached Whitbread regarding a buyout of the firm include Bain Capital, CVC and TPG, insiders have said.
When announcing the split, Whitbread's chief executive Alison Brittain said: "We have carefully considered the optimal timing and concluded that it will be pursued as fast as practical and appropriate to optimise value for Whitbread's shareholders and is expected to be completed within 24 months. This will allow both Premier Inn and Costa to maintain momentum, complete critical and complex transformation and infrastructure objectives, and drive international expansion."