The new Los Angeles office will be headed by Rebecca Hess, who was previously an account director in First Protocol’s New York operation before moving to LA 18 months ago.
Another account director will also join the team initially, with staff rising to around five over the next year, and the aim is to allow First Protocol to deliver events in LA, San Francisco and San Diego more efficiently for their clients.
First Protocol chief executive Richard Waddington said the expansion was part of a five-year growth plan for the agency.
It took over Ryan Fable Productions in Manhattan to form its New York base in 2004.
"We’ve been interested in expanding our delivery capabilities in the US by opening other offices in a key cities and Los Angeles has come up several times in client discussions as a priority for their businesses," said Waddington.
"I’m pleased to say we have weathered the economic downturn extremely well and now see the opportunity for growth; we have a number of plans in the pipeline of which this is the first."
First Protocol’s marketing and business development manager Simon Mogford said the expansion allowed the business to become a "local agency" in the area.
"It will be organic growth as we establish ourselves there," he added. "This is very exciting as it opens up a whole new area of potential business prospects and also allows us to service our current clients’ programmes more cost effectively when looking to host events on the West Coast."