EXHIBIT 11.1 MASSBANK CORP. Earnings Per Share The following is a calculation of earnings per share for the three months and nine months ended September 30, 1997 and 1996. Three Months Ended Nine Months Ended Calculation of Primary September 30, September 30, Earnings Per Share 1997 1996 1997 1996 ______________________________ ____ ____ ____ ____ Average common shares outstanding 3,572,418 3,587,247 3,578,807 3,629,181 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (52,800) (61,600) (52,800) (61,600) Shares assumed to be repurchased under treasury stock method for stock options 150,963 95,838 130,764 100,692 _______ _______ _______ _______ Total Shares 3,670,581 3,621,485 3,656,771 3,668,273 __________ __________ _________ _________ Net Income $2,589,000 $2,444,000 $7,511,000 $7,037,000 __________ __________ __________ __________ Per Share Amount $ 0.70 $ 0.67 $ 2.05 $ 1.92 __________ __________ __________ __________ Three Months Ended Nine Months Ended Calculation of Fully Diluted September 30, September 30, Earnings Per Share 1997 1996 1997 1996 ______________________________ ____ ____ ____ ____ Average common shares outstanding 3,572,418 3,587,247 3,578,807 3,629,181 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (52,800) (61,600) (52,800) (61,600) Shares assumed to be repurchased under treasury stock method for stock options 170,639 96,665 143,959 101,426 ________ _______ _______ _______ Total Shares 3,690,257 3,622,312 3,669,966 3,669,007 _________ _________ _________ _________ Net Income $2,589,000 $2,444,000 $7,511,000 $7,037,000 __________ __________ __________ __________ Per Share Amount $ 0.70 $ 0.67 $ 2.05 $ 1.92