White will establish the agency's presence in Edinburgh and joins from Black to White PR, the consultancy he founded in 2009.
The agency's existing clients, including wealth management firm Fiscal Engineers and the Irish Fund Investment Association, will continue with Broadgate Mainland.
White has spent 30 years in the financial services industry, including spells heading the external comms functions at Aegon UK and Standard Life. He will take up his position with immediate effect and will operate from an Edinburgh base. He will also look to recruit a team for Broadgate Mainland in Scotland as the business grows.