Gardner, Mass.-based Colonial Co-operative Bank merged into Leominster, Mass.-based Fidelity Co-operative Bank, effective April 1, according to an April 27 merger guide for Colonial Co-operative Bank clients.

The Massachusetts Division of Banks approved the merger on March 2.

As of March 31, Fidelity Co-operative Bank had approximately $822.3 million in assets, while Colonial Co-operative Bank had approximately $65.4 million in assets.

Fidelity Co-operative Bank is a unit of Life Design Holding Co., and Fidelity Mutual Holding Co. is the bank's ultimate parent.