##### 



Exhibit 12

Statement Regarding Computation of Ratios

The ratios of income to fixed charges have been computed on the basis of the
total enterprise (as defined by the Commission) by dividing income from continuing operations before fixed
charges and income taxes by fixed charges. Fixed charges consist of interest
expense on all long-term and short-term borrowings, excluding or including
interest on deposits as indicated below. The computations of other ratios are
evident from the information presented in this Form 10-K and the Corporations
2003 Annual Report.

Bank One Corporation and Subsidiaries
Computations of Consolidated Ratios of Earnings to Fixed Charges

|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |   |        | 
|-------------------------------------------------------------------------------- | -------------------------------------------------------------------------------- | --------------------------------------------------------------------------- | ---- | ----------------------------- | ----- | ----- | ----- | ------- | ----- | ----- | ------ | ----- | ----- | ----- | ------ | ---- | ------ | - | ------ | ---- | ----- | - | ------ | 
|                                                                                 |                                                                                  |                                                                             |      |                               |       | Year  |       | Year    |       | Year  |        | Year  |       | Year 
|                                                                                 |                                                                                  |                                                                             |      |                               |       | Ended |       | Ended   |       | Ended |        | Ended |       | Ended
|(In millions, except ratios)                                                     |                                                                                  | 2003                                                                        |      | 2002                          |       | 2001  |       | 2000(1) |       | 1999 
|EXCLUDING INTEREST ON DEPOSITS                                                   |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |     
|                                                                                 |                                                                                  | Pretax income from continuing operations                                    |      | $                             | 4,390 |       |       | $       | 4,702 |       |        | $     | 3,748 |       |        | $    | (1,119 | ) |        | $    | 4,932 |  
|                                                                                 |                                                                                  | Earnings from unconsolidated entities under
the equity method of accounting |      |                               | 140   |       |       |         | 91    |       |        |       | (80   | )     |        |      | (129   | ) |        |      | (47   | )
|                                                                                 |                                                                                  | Fixed charges, excluding capitalized interest                               |      |                               | 2,585 |       |       |         | 2,720 |       |        |       | 3,867 |       |        |      | 5,198  |   |        |      | 3,719 |  
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  |                                                                             |      | Adjusted pretax earnings base |       |       | 7,115 |         |       |       | 7,513  |       |       |       | 7,535  |      |        |   | 3,950  |      |       |   | 8,604  | 
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  | Interest, excluding interest on deposits                                    |      |                               | 2,481 |       |       |         | 2,621 |       |        |       | 3,771 |       |        |      | 5,105  |   |        |      | 3,622 |  
|                                                                                 |                                                                                  | Rental factor                                                               |      |                               | 104   |       |       |         | 99    |       |        |       | 96    |       |        |      | 93     |   |        |      | 97    |  
|                                                                                 |                                                                                  | Capitalized interest                                                        |      |                               | 2     |       |       |         | 1     |       |        |       | 4     |       |        |      | 9      |   |        |      | 2     |  
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  |                                                                             |      | Fixed charges                 |       |       | 2,587 |         |       |       | 2,721  |       |       |       | 3,871  |      |        |   | 5,207  |      |       |   | 3,721  | 
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|Consolidated ratios of earnings to fixed
charges, excluding interest on deposits |                                                                                  |                                                                             | 2.8x |                               |       |       | 2.8x  |         |       |       | 1.9x   |       |       |       | 0.8x   |      |        |   | 2.3x   |     
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|INCLUDING INTEREST ON DEPOSITS                                                   |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |     
|                                                                                 |                                                                                  | Pretax income from continuing operations                                    |      | $                             | 4,390 |       |       | $       | 4,702 |       |        | $     | 3,748 |       |        | $    | (1,119 | ) |        | $    | 4,932 |  
|                                                                                 |                                                                                  | Earnings from unconsolidated entities under
the equity method of accounting |      |                               | 140   |       |       |         | 91    |       |        |       | (80   | )     |        |      | (129   | ) |        |      | (47   | )
|                                                                                 |                                                                                  | Fixed charges, excluding capitalized interest                               |      |                               | 4,616 |       |       |         | 5,431 |       |        |       | 8,748 |       |        |      | 11,322 |   |        |      | 8,357 |  
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  |                                                                             |      | Adjusted pretax earnings base |       |       | 9,146 |         |       |       | 10,224 |       |       |       | 12,416 |      |        |   | 10,074 |      |       |   | 13,242 | 
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  | Interest, including interest on deposits                                    |      |                               | 4,512 |       |       |         | 5,332 |       |        |       | 8,652 |       |        |      | 11,229 |   |        |      | 8,260 |  
|                                                                                 |                                                                                  | Rental factor                                                               |      |                               | 104   |       |       |         | 99    |       |        |       | 96    |       |        |      | 93     |   |        |      | 97    |  
|                                                                                 |                                                                                  | Capitalized interest                                                        |      |                               | 2     |       |       |         | 1     |       |        |       | 4     |       |        |      | 9      |   |        |      | 2     |  
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 |                                                                                  |                                                                             |      | Fixed charges                 |       |       | 4,618 |         |       |       | 5,432  |       |       |       | 8,752  |      |        |   | 11,331 |      |       |   | 8,359  | 
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  
|                                                                                 | Consolidated ratios of earnings to fixed charges, including interest on deposits |                                                                             |      | 2.0x                          |       |       |       | 1.9x    |       |       |        | 1.4x  |       |       |        | 0.9x |        |   |        | 1.6x |      
|                                                                                 |                                                                                  |                                                                             |      |                               |       |       |       |         |       |       |        |       |       |       |        |      |        |   |        |      |       |  

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|(1)   Results
for the year ended December 31, 2000 were insufficient to cover
fixed charges. The coverage deficiency was
        approximately
$1.3 billion.