CAMDEN — Camden National Bank is buying 15 Bank of America branches across Maine.

The Camden-based bank announced today that the deal will expand its branch count to 53. The acquisition is subject to federal approval.

The acquisition includes Bank of America branches in Auburn, Brewer, Gardiner, Lewiston, Newport, Old Town, Rockland and Waterville, as well as three branches both in the Augusta and Bangor areas.

Camden National President and CEO Gregory Dufour told the Bangor Daily News that once the $20 million deal is completed, his bank will have the largest share of deposits held by any Maine-based community bank.

He said the acquisition will bring the bank’s work force to more than 500, up from about 425 now.