EXHIBIT 12 3M COMPANY AND SUBSIDIARIES

CALCULATION OF RATIO OF EARNINGS TO FIXED CHARGES (Dollars in millions) 2002 2001 2000 1999 1998 EARNINGS Income from continuing operations before income taxes, minority interest, extraordinary loss and cumulative effect of accounting change* $3,005 $2,186 $2,974 $2,880 $1,952 Add: Interest expense 100 143 127 125 139 Interest component of the ESOP benefit expense 16 18 19 21 29 Portion of rent under operating leases representative of the interest component 40 39 39 37 41 Less: Equity in undistributed income of 20-50 percent owned companies 10 5 10 4 4 TOTAL EARNINGS AVAILABLE FOR FIXED CHARGES $3,151 $2,381 $3,149 $3,059 $2,157 FIXED CHARGES Interest on debt 100 150 141 135 139 Interest component of the ESOP benefit expense 16 18 19 21 29 Portion of rent under operating leases representative of the interest component 40 39 39 37 41 TOTAL FIXED CHARGES $ 156 $ 207 $ 199 $ 193 $ 209 RATIO OF EARNINGS TO FIXED CHARGES 20.2 11.5 15.8 15.8 10.3 * 2002 and 2001, includes a non-recurring net pre-tax losses of $202 million and $504 million, respectively, primarily related to the restructuring. 2000 includes non-recurring net pre-tax losses of $23 million. 1999 includes non- recurring net pre-tax gains of $100 million relating to gains on divestitures, litigation expense, an investment valuation adjustment, and a change in estimate that reduced 1998 restructuring charges. 1998 includes pre-tax restructuring charges of $493 million.