EXHIBIT 11.1 MASSBANK CORP. Earnings Per Share The following is a calculation of earnings per share for the three months ended March 31, 1999 and 1998. Three Months Ended Calculation of Basic March 31, Earnings Per Share 1999 1998 ______________________________ __________ __________ Net Income $2,913,000 $2,834,000 _________ _________ Average common shares outstanding 3,486,088 3,578,654 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (35,200) (44,000) __________ _________ Weighted average shares outstanding 3,450,888 3,534,654 __________ _________ Earnings per share (in dollars) $ 0.84 $ 0.80 __________ __________ Three Months Ended Calculation of Diluted March 31, Earnings Per Share 1999 1998 ______________________________ __________ __________ Net Income $2,913,000 $2,834,000 __________ __________ Average common shares outstanding 3,486,088 3,578,654 Less: Unallocated Employee Stock Ownership Plan (ESOP) shares not committed to be released (35,200) (44,000) Diluted stsock options 116,425 161,930 __________ __________ Weighted average shares outstanding 3,567,313 3,696,584 __________ __________ Earnings per share (in dollars) $ 0.82 $ 0.77 __________ __________