King left RBC this past summer after a five-year run having joined from Barclays Wealth in 2010.
Earlier in his career he spent time at firms including Alliance Bernstein and Credit Suisse.
Maseco is focused on “wealth management tailored to the needs and concerns of Americans in the UK”.
It offers bespoke portfolios and works with firms in the UK, US, Switzerland and Singapore to achieve, tax, cost and investment goals for clients.
