The National Theatre is set to change the name of the smallest of its three theatres from the Cottesloe to the Dorfman following a £10 million personal donation by Lloyd Dorfman. The currency exchange millionare, who is founder and chairman of Travelex and a member of the National's board, makes a major contribution to the NT Future redevelopment fund, which aims to raise £70 million.

As previously reported, the NT Future campaign will see the National refurbish and expand the NT Cottesloe, soon Dorfman, with the addition of an education centre and the construction of a new cafe and glass-fronted production building.

Dorfman, who founded the foreign exchange business with a single shop in 1976 and is now estimated to have a personal fortune of £520 million, was a key figure in establishing the National's Travelex £10 Ticket. The relationship, which was formed in 2003 and was renewed for a further three years from 2010, saw its millionth ticket sold this summer and has been worth in excess of £2 million to the National.

The NT Cottesloe was originally named after John Fretmantle, the fourth Baron Cottesloe, who was a key advocate for the creation of the National Theatre, and who died in 1994. His name was initially intended to be given to an experimental theatre space, but was appended to a public theatre when the National's then director, Peter Hall, realised that the building could accommodate three performance spaces.

News of the donation comes after Nicholas Hytner, the director of the National spoke out against a move to an American style, fully philanthropic arts funding environment in the foreword to this year's National Theatre Annual Report.

The auditorium of the new NT Dorfman will be refurbished to extend capacity, creating at least 10,000 new seats a year. Depending on the success of the NT Futures fundraising campaign, the National aims to start building works in Spring 2012 with a completion date at the end of 2014.