Hornblower UK Holdings, based in San Francisco, is taking over the river Thames operator from former chairman and chief executive, Gary and Rita Beckwith.
It said all City Cruises staff would be retained with the Beckwiths staying on as consultants for several months to help with the transition.
Gary said: “We believe the sale of City Cruises to the Hornblower family of brands will take the brand to the next level of success.
