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                                                     Exhibit (12)
                                                     Commonwealth Edison Company
                                                     Form 10-Q File No. 1-1839



       Commonwealth Edison Company and Subsidiary Companies Consolidated

              Computation of Ratios of Earnings to Fixed Charges
                  and Ratios of Earnings to Fixed Charges and
             Preferred and Preference Stock Dividend Requirements

                            (Thousands of Dollars)
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<CAPTION>
 


                                                                                  Twelve Months Ended
                                                                                ------------------------
 Line                                                                           March 31,    December 31,
  No.                                                                              1997          1996
 ----                                                                           ----------   ------------
<S>  <C>                                                                        <C>          <C>
  1  Net income                                                                 $  714,152    $  743,368
                                                                                ----------    ----------
  2  Net provisions for income taxes and investment tax credits deferred   
  3    charged to-                                                        
  4      Operations                                                             $  445,369    $  462,402
  5      Other income                                                               (3,543)       (7,385)
                                                                                ----------    ----------
                                                                              
  6                                                                             $  441,826    $  455,017
                                                                                ----------    ----------
                                                                              
                                                                            
  7  Fixed charges-                                                     
  8    Interest on debt                                                         $  516,382    $  523,310
  9    Estimated interest component of nuclear fuel and                     
 10      other lease payments, rentals and other interest                           70,780        70,666
 11    Amortization of debt discount, premium and expense                           21,056        21,151
 12    Preferred securities dividend requirements of subsidiary trusts              19,368        16,960
                                                                                ----------    ----------
                                                                              
 13                                                                             $  627,586    $  632,087
                                                                                ----------    ----------
                                                                          
 14  Preferred and preference stock dividend requirements-                  
 15    Provisions for preferred and preference stock dividends                  $   63,437    $   64,424
 16    Taxes on income required to meet provisions for                      
 17      preferred and preference stock dividends                                   41,488        42,150
                                                                                ----------    ----------
                                                                              
 18                                                                             $  104,925    $  106,574
                                                                                ----------    ----------
                                                                          
 19  Fixed charges and preferred and preference stock                         
 20    dividend requirements                                                    $  732,511    $  738,661
                                                                                ----------    ----------
                                                                              
 21  Earned for fixed charges and preferred and preference stock            
 22    dividend requirements                                                    $1,783,564    $1,830,472
                                                                                ----------    ----------
                                                                              
 23  Ratios of earnings to fixed charges (line 22 divided by line 13)                 2.84          2.90
                                                                                      ====          ====
                                                                                
 24  Ratios of earnings to fixed charges and preferred and preference     
 25    stock dividend requirements (line 22 divided by line 20)                       2.43          2.48
                                                                                      ====          ====   
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