EXHIBIT 11.1 MASSBANK CORP. Earnings Per Share The following is a calculation of earnings per share for the three and six months ended June 30, 1999 and 1998. Three Months Ended Six Months Ended Calculation of Basic June 30, June 30, Earnings Per Share 1999 1998 1999 1998 ______________________________ ____ ____ ____ ____ Net Income $2,866,000 $2,706,000 $5,779,000 $5,540,000 _________ _________ _________ _________ Average common shares outstanding 3,414,996 3,590,194 3,450,346 3,584,456 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (35,200) (44,000) (35,200) (44,000) __________ _________ __________ ________ Weighted average shares outstanding 3,379,796 3,546,194 3,415,146 3,540,456 _________ _________ _________ _________ Earnings per share (in dollars) $ 0.85 $ 0.76 $ 1.69 $ 1.56 _________ _________ _________ _________ Three Months Ended Six Months Ended Calculation of Diluted June 30, June 30, Earnings Per Share 1999 1998 1999 1998 ______________________________ ____ ____ ____ ____ Net Income $2,866,000 $2,706,000 $5,779,000 $5,540,000 _________ _________ _________ _________ Average common shares outstanding 3,414,996 3,590,194 3,450,346 3,584,456 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (35,200) (44,000) (35,200) (44,000) Diluted stock options 115,822 162,507 116,121 162,220 _________ _________ _________ _______ Weighted average shares outstanding 3,495,618 3,708,701 3,531,267 3,702,676 _________ _________ _________ _________ Earnings per share (in dollars) $ 0.82 $ 0.73 $ 1.64 $ 1.50 _________ __________ __________ __________