Exhibit 12(b)

                            Aon Corporation and Consolidated Subsidiaries
                              Combined With Unconsolidated Subsidiaries
                     Computation of Ratio of Earnings to Combined Fixed Charges
                                    and Preferred Stock Dividends


                                              Nine Months Ended
                                                September 30,          Years Ended December 31,
                                                --------------  --------------------------------------
 (millions except ratios)                        1998    1997    1997   1996    1995    1994    1993
                                                ------- ------  ------ ------- ------  ------ --------
                                                                         
 Income from continuing operations
    before provision for income taxes (1)       $692.3  $344.9  $541.6 $445.6  $458.0  $397.0  $331.6

 Add back fixed charges:

    Interest on indebtedness                      63.5    49.3    69.5   44.7    55.5    46.4    42.3

    Interest on ESOP                               2.0     2.8     3.5    4.3     5.3     5.9     6.5

    Portion of rents representative of
      interest factor                             33.2    44.2    44.3   28.6    21.4    28.7    26.1

                                                ------- ------  ------ ------- ------- ------- -------
         Income as adjusted                     $791.0  $441.2  $658.9 $523.2  $540.2  $478.0  $406.5
                                                ======= ======  ====== ======= ======= ======= =======


 Fixed charges and preferred stock dividends:

    Interest on indebtedness                    $ 63.5  $ 49.3  $ 69.5 $ 44.7  $ 55.5  $ 46.4  $ 42.3

    Preferred stock dividends                     52.3    63.6    82.1   28.7    37.5    48.4    47.5

                                                -------  ------  ------ ------- ------  ------ -------
         Interest and dividends                  115.8   112.9   151.6   73.4    93.0    94.8    89.8
                                                                                 
    Interest on ESOP                               2.0     2.8     3.5    4.3     5.3     5.9     6.5

    Portion of rents representative of
       interest factor                            33.2    44.2    44.3   28.6    21.4    28.7    26.1

         Total fixed charges and preferred
                                                ------- ------  ------ ------- -------  ------ -------
             stock dividends                    $151.0  $159.9  $199.4 $106.3  $119.7  $129.4  $122.4
                                                ======= ======  ====== ======= =======  ====== =======

 Ratio of earnings to combined fixed
   charges and preferred stock dividends (2)       5.2     2.8     3.3    4.9     4.5     3.7     3.3
                                                ======= ======  ====== ======= =======  ====== =======

 Ratio of earnings to combined fixed
   charges and preferred stock dividends (3)              3.8     4.2     5.8
                                                        ======  ====== =======


<FN>
(1)   Income from continuing  operations  before  provision for income taxes and
      minority  interest  includes  special charges of $172 million for the nine
      months ended  September 30, 1997 and the year ended December 31, 1997, and
      $90.5 million for the year ended December 31, 1996.

(2)   Included in total fixed charges and preferred stock dividends for the nine
      months  ended  September  30,  1998  and  1997 are  $49  million  and  $48
      million,  respectively,  and $64 million for the year ended  December  31,
      1997  of  pretax  distributions  on  the  8.205%  mandatorily   redeemable
      preferred capital  securities which are classified as "minority  interest"
      on the condensed consolidated statements of operations.

(3)   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  nine  months  ended
      September  30,  1997 and for the years ended  December  31, 1997 and 1996,
      respectively.
</FN>