Opened by restaurateur Mascarenhas in 1986 – when it was just known as Sonny’s – it specialised in Modern European cuisine.
It went on to be rebranded as Sonny’s Kitchen in 2014, after Mascarenhas joined forces with chef Phil Howard.
The pair continue to co-own the Michelin-starred Elystan Street and Kitchen W8 restaurants, located in Chelsea and Kensington respectively.
Mascarenhas, who tends to play a behind the scenes role in her projects, also owns Home SW15 in Putney.
The reason behind the closure is yet to be released, but in a statement it was confirmed that news regarding the next stage of the Barnes restaurant will be announced in the coming months.
Speaking to BigHospitality back in 2013, Mascarenhas said she chose Barnes as the location for her first restaurant as she did not have the capital to invest in a central London restaurant.
“I was convinced there was a market on the doorstep for the same people who went to restaurants in Mayfair, Kensington and Chelsea,” she said.
“It was the same demographic, but they wanted something closer to home.”
Her recent projects include partnering with the team behind wine-focused restaurant concept Gezellig, which opened in Holborn back in May.