Maybourne Hotel Group's hotel The Connaught, which was given a four-star rating by the US-based guide when it launched in the UK earlier this year, joins 45 Park Lane, Claridge's, Four Seasons Hotel at Park Lane, The Dorchester, The Lanesborough and The Savoy in receiving the guide's top rating.
It means that London now boasts seven Forbes five-star rated hotels, the same number currently listed in Hong Kong and one more than the number offered in New York.
The Connaught's general manager Nathalie Seiler-Hayez said she was 'proud and honoured' that the Mayfair-based hotel had been given Forbes' five-star rating.
"To be included in such a distinguished travel site, and to receive the highest accolade of five stars is most prestigious," she said. "This is recognition of the hard work and dedication by our team who constantly strive to deliver exceptional service experiences and special memories for our guests."
The six month update of the guide also gives four more hotels in the capital a four-star rating - Dorset Square, Dukes, The Halkin and St Ermin's - boosting the number of hotels in this category in London to 18 while another four - Charlotte Street Hotel, Grosvenor House, The Metropolitan and The St Pancras Renaissance- have earned themselves a recommended rating.
Forbes Travel Guide president Michael Cascone said star rating coverage was 'rapidly expanding' due to continual rising service standards in London's hotels.
“Our goal is to recognise the properties that are committed to delivering the finest guest experiences worldwide. We’re proud to be associated with the new additions to our global list,” he added.
Inspectors for Forbes Travel Guide which was founded in 1958, measure hotels against 500 standards which look at facility and service performance with guest engagement and service delivery accounting for 70 per cent of the marks.
The Guide's launch into the UK earlier this year will be followed by a launch into Paris next year.