EXHIBIT 11 FIRST KEYSTONE CORPORATION COMPUTATION OF EARNINGS PER COMMON SHARE Nine Month Period Ended September 30, 2002 and 2001 (Dollars in Thousands) 2002 2001 <s> <c> <c> Primary Net Income $ 4,939 $ 3,854 Shares Weighted average number of common shares outstanding 2,974,288 2,975,180 Adjustments - increases or decreases None None Weighted average number of common shares outstanding as adjusted 2,974,288 2,975,180 Primary earnings per common share $ 1.66 $ 1.30 Assuming full dilution Net Income $ 4,939 $ 3,854 Shares Weighted average number of common shares outstanding 2,974,288 2,975,180 Adjustments - increases or decreases None None Weighted average number of common shares outstanding as adjusted 2,974,288 2,975,180 Earnings per common share assuming full dilution $ 1.66 $ 1.30 45: 23