EXHIBIT 11 Washington Trust Bancorp, Inc. Computation of Per Share Earnings For the Nine Months Ended September 30, 1997 and 1996 Three Months Nine Months --------------------------- ---------------------------- Periods ended September 30, 1997 1996 1997 1996 - ------------------------------------------------- ----------------- --------- ----------------- ---------- (In thousands, except per share amounts) Primary: Weighted average shares 4,394.1 4,345.7 4,382.4 4,315.3 Common stock equivalents 154.3 157.8 161.3 144.5 ------------- ------------- -------------- ------------- Primary weighted average shares 4,548.4 4,503.5 4,543.7 4,459.8 ------------- ------------- ------------- -------------- Fully diluted: Weighted average shares 4,394.1 4,345.7 4,382.4 4,315.3 Common stock equivalents 156.4 167.9 167.0 170.5 ------------- ------------- ------------- -------------- Fully diluted weighted average shares 4,550.5 4,513.6 4,549.4 4,485.8 ------------- ------------- ------------- -------------- Net income $2,364 $2,321 $6,776 $6,357 ------------- ------------- ------------- -------------- Primary earnings per share $.52 $.52 $1.49 $1.43 ------------- ------------- ------------- -------------- Fully diluted earnings per share $.52 $.51 $1.49 $1.42 ------------- ------------- ------------- --------------