Ion Financial in Naugatuck, Conn., has agreed to absorb Cooperative Bank in Boston.
The $2.8 billion-asset Ion said in a press release that the $540 million-asset Cooperative will continue to operate as a division.
Cooperative President and CEO John Battaglia will join Ion as president of the new division.
The banks will create a $2.5 million charitable foundation to support local communities served by the Massachusetts branches.
Performance Trust Capital Partners advised Ion.