EXHIBIT 12(a) BANKBOSTON CORPORATION COMPUTATION OF CONSOLIDATED RATIO OF EARNINGS TO FIXED CHARGES (Excluding Interest on Deposits) The Corporation's ratios of earnings to fixed charges (excluding interest on deposits) for the five years ended December 31, 1998 were as follows: Years Ended December 31, ------------------------ (Dollars in millions) 1998 1997 1996 1995 1994 ----- ----- ----- ----- ----- Net income $ 792 $ 879 $ 650 $ 678 $ 542 Extraordinary item, net of tax 7 Income tax expense 477 589 483 529 422 ------- ------- ------- ------- ------- Pretax earnings 1,269 1,468 1,133 1,207 971 ------- ------- ------- ------- ------- Fixed charges: Portion of rental expense (net of sublease rental income) which approximates the interest factor 42 39 40 38 35 Interest on borrowed funds 1,179 1,050 873 1,079 1,038 ------- ------- ------- ------- ------- Total fixed charges 1,221 1,089 913 1,117 1,073 ------- ------- ------- ------- ------- Earnings (for ratio calculation) $ 2,490 $ 2,557 $ 2,046 $ 2,324 $ 2,044 ======= ======= ======= ======= ======= Total fixed charges $ 1,221 $ 1,089 $ 913 $ 1,117 $ 1,073 ======= ======= ======= ======= ======= Ratio of earnings to fixed charges 2.04 2.35 2.24 2.08 1.90 ======= ======= ======= ======= ======= For purposes of computing the consolidated ratio of earnings to fixed charges, "earnings" represent income before extraordinary item plus applicable income taxes and fixed charges. "Fixed charges" include gross interest expense (excluding interest on deposits) and the proportion deemed representative of the interest factor of rent expense, net of income from subleases.