The deal sees SBE UK properties St Martins Lane, Sanderson London and The Mondrian at Sea Containers – home to the Dandelyan bar – join Accor’s booking site and loyalty programme.
SBE's luxury hospitality portfolio includes the largely US-based Disruptive Restaurant group, which runs several sites in partnership with chefs Jose Andres and Michael Schwartz.
Accor will acquire a 50% stake in SBE's common equity held by Cain International for $125m, and invest $194m in a new preferred debt instrument – amounting to a total investment of $319m.
It says the partnership will give it access to SBE's core millennial customer base while fuelling the group’s expansion in Europe and worldwide.
The deal is the latest in a string of acquisitions by Accor, which bought restaurant reservation service ResDiary in April.
Its portfolio includes The Savoy in London and The Plaza in New York, which it acquired after buying its parent company FRHI for £1.9bn in 2016.
“[This investment] supports our collective ambition to be the best lifestyle hospitality company in the market,” says SBE founder Sam Nazarian, who will continue to lead the New York-based company.
“[It] will further accelerate our growth both domestically in the United States and in new markets internationally, particularly in Europe.”
The transaction is subject to regulatory approvals, but should be completed by 31 July 2018.