The two musical icons joined forces at the legend's 70th in Los Angeles over the weekend.
Lady Gaga and Tony Bennett have added an extra show at London's Royal Albert Hall.
The pair will now perform a second night at the iconic venue on Tuesday, June 9 following high demand for tickets to their June 8 show.
Lady Gaga and Tony Bennett will perform two shows in London next summer
The shows will see Gaga and Bennett perform songs from their collaborative album Cheek to Cheek, accompanied by a big band and an orchestra.
The concerts are being held in support of WellChild, the national charity for seriously ill children.
The Chief Executive of WellChild, Colin Dyer, said: "WellChild is thrilled that Lady Gaga and Tony Bennett are supporting WellChild through this concert.
"The proceeds will be a massive boost to our work to support seriously ill children and their families across the UK."
Tickets for their second Royal Albert Hall show are on sale from Friday, November 7 at 9am and are priced between £45 and £130.
Watch the music video for 'Anything Goes' below: