Aon Corporation and Consolidated Subsidiaries                                                 Exhibit 12(b)
                    Combined With Unconsolidated Subsidiaries
                Computation of Ratio of Earnings to Fixed Charges
                               and Preferred Stock Dividends

                                                                     
                                                                      
                                                                      Six Months
                                                                     Ended June 30,            Years Ended December 31,
                                                                    ---------------   ---------------------------------------------
(millions except ratios)                                             1997     1996     1996     1995     1994    1993     1992 (1)
                                                                    ------   ------   ------   ------   ------   ------   ---------
                                                                                                        
Income from continuing operations
  before provision for income taxes (2) .........................   $167.1   $246.9   $445.6   $458.0   $397.0   $331.6   $179.1



Add back fixed charges:

Interest on indebtedness ........................................     30.6     23.9     44.7     55.5     46.4     42.3     41.9

Interest on ESOP ................................................      1.9      2.4      4.3      5.3      5.9      6.5      6.9

Portion of rents representative of
  interest factor ...............................................     29.4     13.4     28.6     21.4     28.7     26.1     19.2
                                                                    ------   ------   ------   -------  ------   ------   -------
     Income as adjusted .........................................   $229.0   $286.6   $523.2   $540.2   $478.0   $406.5   $247.1
                                                                    ======   ======   ======   =======  ======   ======   =======

Fixed charges:

Interest on indebtedness ........................................   $ 30.6   $ 23.9   $ 44.7   $ 55.5   $ 46.4   $ 42.3   $ 41.9
 
Preferred stock dividends........................................     42.0     15.7     28.7     37.5     48.4     47.5     20.3
                                                                     -----   ------   ------   ------   ------   ------   ------ 
                                                                     
   Interest and dividends........................................     72.6     39.6     73.4     93.0     94.8     89.8      62.2
                                                                     
Interest on ESOP ................................................      1.9      2.4      4.3      5.3      5.9      6.5      6.9

Portion of rents representative of
  interest factor ...............................................     29.4     13.4     28.6     21.4     28.7     26.1     19.2
                                                                    -------  ------   ------   -------  ------   ------   -------
     Total fixed charges and preferred
       stock dividends.. ........................................   $103.9   $ 55.4   $106.3   $119.7   $129.4   $122.4   $ 88.3
                                                                    =======  ======   ======   =======  ======   ======   =======
        
Ratio of earnings to combined fixed
  charges and preferred stock dividends (3)......................      2.2      5.2      4.9      4.5      3.7      3.3      2.8
                                                                    =======  =======  ======   =======  ======   ======   =======

Ratio of earnings to combined fixed
  charges and preferred stock dividends (4)......................      3.9      5.7      5.8                                 3.8
                                                                    =======  =======  ======                              =======

                                     
<FN>
(1)  Income  from  continuing  operations  before  provision  for  income  taxes
     excludes the cumulative effect of changes in accounting principles.
(2)  Income from  continuing  operations  before  provision for income taxes and
     minority  interest  includes  special  charges  of $172  million  and $30.2
     million  for six months  ended June 30, 1997 and 1996 ,  respectively,  and
     $90.5  million and $86.5  million in the years ended  December 31, 1996 and
     1992, respectively.
(3)  Included in total fixed charges and preferred stock dividends for  the  six
     months ended June 30, 1997 are $31.2 million of pretax distributions on the
     8.205% trust preferred capital securities which are classified as "minority
     interest" on the condensed cosolidated statements of operations.    
(4)  The  calculation  of this ratio of earnings to fixed  charges  reflects the
     exclusion  of special  charges from the income from  continuing  operations
     before  provision for income taxes  component for the six months ended June
     30, 1997 and 1996, respectively,  and the years ended December 31, 1996 and
     1992, respectively.
</FN>