Natick-based Middlesex Savings Bank and Strata Bank of Medway have signed an agreement and plan of merger, under which Strata Bank will be merged into Middlesex Savings Bank.

Pursuant to the agreement, the mutual holding company structure of Service Bancorp MHC will be eliminated and Strata Bank will re-mutualize and merge with Middlesex Savings Bank, the companies said in a statement. The public stockholders of Service Bancorp Inc. will receive $28 per share.

Middlesex Savings Bank is a Massachusetts savings bank. Strata Bank is a Massachusetts stock savings bank, which is wholly owned by Service Bancorp Inc., a majority owned subsidiary of Service Bancorp MHC, a Massachusetts mutual holding company.