City National Corp., parent of Los Angeles County’s largest locally based bank, said it has moved its headquarters and that of City National Bank from Beverly Hills to downtown Los Angeles.

City National Plaza, the new location, has been home to the bank holding company’s administrative center since 2004, the company said Thursday. City National leases approximately 381,000 square feet of commercial space on 15 floors at the 51-story building located at 555 South Flower Street.

City National Center in Beverly Hills, the corporate headquarters since 1955, will continue to house the bank’s entertainment and wealth management divisions, its personal trust and Westside private client services units, and the Beverly Hills banking office, City National said.

“This is a logical evolution in the growth of City National,” Chief Executive Russell Goldsmith said in a statement, noting that the company has 1,000 of its 2,900 colleagues already working downtown, more than in any other single location.