EXHIBIT 11 Washington Trust Bancorp, Inc. Computation of Per Share Earnings For the Three Months Ended March 31, 1998 and 1997 (In thousands, except per share amounts) 1998 1997 - ----------------------------------------------------------------------- ------------------------- Basic Diluted Basic Diluted ------------ ------------ ------------ ------------ Net income $2,393 $2,393 $2,151 $2,151 Share amounts, in thousands: Average outstanding 6,649.3 6,649.3 6,549.4 6,549.4 Common stock equivalents - 274.4 - 264.3 - --------------------------------------------- ------------ ------------ ------------ ------------ Weighted average outstanding 6,649.3 6,923.7 6,549.4 6,813.7 - --------------------------------------------- ------------ ------------ ------------ ------------ Earnings per share $.36 $.35 $.33 $.32 - --------------------------------------------- ------------ ------------ ------------ ------------