EXHIBIT 11 FIRST BELL BANCORP, INC. COMPUTATION OF PRIMARY AND FULLY DILUTED EARNINGS PER SHARE FOR THE NINE AND THREE MONTHS ENDED SEPTEMBER 30, 2001 (in thousands, except per share amounts) (unaudited) Nine Months Ended September 30, 2001 Weighted Average Per Income Shares Share ------ ------ ----- Income available to common stockholders $4,487 4,758 - Unearned MRP shares - (181) - Unearned ESOP shares - (486) - --------- ------ ------- Basic earnings per share 4,487 4,092 $1.10 Effect of dilutive securities: Stock options - 99 - ---------- ------- ------- Diluted earnings per share $4,487 4,191 $1.07 ========== ======= ======= Three Months Ended September 30, 2001 Weighted Average Per Income Shares Share ------ ------ ----- Income available to common stockholders $1,464 4,758 - Unearned MRP shares - (181) - Unearned ESOP shares - (478) - --------- ----- -------- Basic earnings per share 1,464 4,099 $0.36 Effect of dilutive securities: Stock options - 102 - --------- --------- -------- Diluted earnings per share $1,464 4,201 $0.35 ========= ========= ========