<Page>


                                                                      Exhibit 99

AON REPORTS THIRD QUARTER 2001 EARNINGS;
UPDATES ON BUSINESS TRANSFORMATION,
IMPACT OF SEPTEMBER 11 ATTACKS AND SPIN-OFF PLANS

Chicago, IL - November 7, 2001 -- Aon Corporation (NYSE: AOC) today reported
third quarter dilutive earnings per share of $0.38 before charges related to the
events of September 11, 2001, compared with $0.53 in third quarter 2000.
Excluding September 11 charges and non-operating corporate segment revenue,
third quarter 2001 dilutive earnings were $0.37 per share versus $0.47 per share
a year ago. Reported net income and dilutive earnings per share for third
quarter 2001 were $72 million and $0.26, respectively, compared with $139
million and $0.53 in the year ago period. September 11 related charges not
covered by the Company's insurance program were $53 million pretax in the third
quarter or $0.12 per share.

The Company stated in its September 17th press release that third quarter
earnings would be unfavorably impacted by the events of September 11, slower
revenue growth in U.S. retail brokerage business due to the implementation of
the business transformation plan, and slower organic revenue growth in the
Consulting segment.

Patrick G. Ryan, chairman and CEO, said, "There were unanticipated challenges
and delays in certain parts of our U.S. retail business transformation process
that were compounded by the September 11 attacks on the World Trade Center.
Client service is our primary focus and we have incurred additional costs,
including expenses to run parallel systems longer than we expected. A concerted
effort is being made to finish conversions to the new operating platform that
will not only enhance client service, but also drive efficiencies. This, in
turn, will increase our capacity to win new accounts and lead to better
financial performance. Tempering this improvement in the near-term will be the
negative influences of the WTC disaster on our Company."

Ryan added, "Most of our individual operating units performed well in the third
quarter and our global franchise remains strong. I am confident about Aon's
long-term success."

DETAILED DISCUSSION OF THIRD QUARTER AND NINE MONTHS FINANCIAL RESULTS
Consolidated revenue of $1.9 billion in the third quarter increased 7% from the
prior year, due in part to acquisitions. Further reductions in short-term
interest rates and unfavorable equity markets negatively impacted investment
income. Adjusting for foreign currency translation, revenue growth was 9%.

Aon's operating segments - Insurance Brokerage and Other Services, Consulting
and Insurance Underwriting - recorded third quarter revenue of $1.9 billion, up
8% from the prior year. Adjusted for foreign currency translation, third quarter
total operating segment revenues increased 10%. Operating segment investment
income decreased $6 million to $102 million from $108 million in third quarter
2000 due partly to declining interest rates. Total operating segment pretax
income, before charges related to the events of September 11, was $262 million
compared with $290 million in third quarter 2000. For the nine months, operating
segment pretax

<Page>

income, before charges from September 11 and special charges related to the
business transformation plan, grew 2% to $855 million, up from $840 million
in 2000. After netting the effect of currency hedges, the impact of foreign
currency translations on net income was not material.

Third quarter reported Insurance Brokerage and Other Services segment revenue
grew 7% to $1.112 billion compared with $1.042 billion in 2000. Adjusted for
foreign currency translation, revenue growth was 8%. Organic revenue growth was
6% in the quarter, principally reflecting slower new business growth in U.S.
retail brokerage due in part to unexpected complications and delays in the
implementation of the business transformation plan and the events of September
11. Claims services and international and wholesale brokerage continued to post
solid revenue growth.

Insurance Brokerage and Other Services pretax income before charges related to
September 11 was $153 million compared with $183 million in third quarter 2000.
The pretax margin in third quarter 2001 was 13.8% compared with 17.6% in the
year ago period. Slower new business growth and higher lost business in U.S.
retail brokerage principally affected margin comparisons. Higher than
anticipated costs, due partly to running parallel systems as part of the
business transformation plan, also contributed to the margin decline. As full
conversions to new processes are completed, these added costs are expected to
lessen starting in second quarter 2002. While lost business was more than year
ago levels, mostly due to voluntary and involuntary employee departures, it was
only slightly more than expectations. Recent hiring of new business development
professionals is expected to improve new account generation in future periods.

Recent acquisitions focused on enhancing Aon's outsourcing capabilities (e.g.
captive management, claims services and safety engineering) also factored into
revenue and expense comparisons. As these new services are assimilated and then
distributed through Aon's global distribution network, they are expected to
positively impact future revenue growth and margin comparisons.

Consulting segment reported revenues rose 27% to $232 million from $182 million
in the year-ago third quarter. This growth included the results of Actuarial
Sciences Associates, Inc. (ASA), acquired in fourth quarter 2000, and ASI
Solutions Incorporated (ASI), acquired in second quarter 2001. Consulting
segment organic revenue growth was 4% for the quarter due to a slowdown in
hiring by some of our clients and the impact of September 11. Pretax income
before September 11 charges rose 12% to $29 million versus $26 million in third
quarter 2000. The Consulting pretax margin was 12.5% in the third quarter versus
14.3% in the year ago period, reflecting the impact of acquisitions and slower
organic revenue growth in the human resources consulting business. The employee
benefits area showed good performance in the quarter.

The recent acquisitions of ASA and ASI give Aon unmatched capabilities to
deliver human resource outsourcing solutions to corporate clients. The Company
expects that demand for these services will grow as companies seek lower cost,
higher quality human capital solutions that improve their overall productivity.

                                       5
<Page>

Insurance Underwriting segment reported revenues increased 5% to $565 million in
third quarter 2001, up from $536 million in third quarter 2000, reflecting the
continued development of new product initiatives and a higher volume of business
in accident and health products. Adjusted for foreign currency translation,
revenues increased 7%.

Insurance Underwriting pretax income before September 11 related charges was $80
million in the third quarter versus $81 million in the prior year period. The
Underwriting pretax margin was 14.2% for the quarter versus 15.1% in third
quarter 2000. A decline in investment income, due in part to lower interest
rates, affected margin comparisons.

Corporate and Other segment revenue, comprised primarily of equity-related
revenues from limited partnerships and directly owned equities, was $3 million
for the quarter compared with $25 million in third quarter 2000. Reduced
Corporate revenue was primarily due to lower increases in limited partnership
values compared to the same quarter a year ago. The Corporate and Other segment
pretax loss for the quarter was $76 million, compared with a pretax loss of $46
million in the prior year quarter due primarily to the decline in Corporate and
Other segment revenue. Corporate segment general expenses increased relative to
the prior year due in part to duplicate occupancy costs involving major moves to
new office space and benefits involving the sale of a business in third quarter
2000.

Total debt at September 30, 2001 was $1.85 billion, down from $2.28 billion at
September 30, 2000.

Nine months 2001 net income and dilutive earnings per share were $120 million
and $0.44, respectively, compared with $384 million and $1.46 in the year ago
period. Excluding 2001 special charges related to the previously announced
business transformation plan of $0.49 per share, charges related to the events
of September 11 of $0.12 per share, and the adoption of SAB 101 in 2000 ($0.03
per share), nine months 2001 earnings were $1.05 per share compared with $1.49
per share in nine months 2000.

The Corporate segment nine months revenue decline of $173 million, or $0.40 per
share, from a positive $77 million to a negative $96 million was a major factor
in the year-over-year decline in earnings per share. Corporate revenue reflects
the performance of the Company's equity investments that were negatively
impacted by stock market declines.

BUSINESS TRANSFORMATION UPDATE
Aon's business transformation plan was announced in November 2000 with goals to
enhance client service, accelerate organic revenue growth and reduce costs. "We
remain convinced that the business transformation plan will produce significant
benefits," Ryan stated. "While we are disappointed by the setbacks in the third
quarter, we believe we will achieve annualized savings of between $150 million
and $200 million in 2002."

In U.S. retail brokerage, the business transformation entailed: process redesign
following the rollout of a new policy management and accounting system, job
redesign based on functional expertise and the creation of four new Client
Service Business Units (CSBUs). Significant implementation steps were taken
through second quarter 2001. These steps included:

                                       6
<Page>

notifications of job eliminations, hiring of new employees at new job grades
and locations, the creation of specialized syndication groups to handle the
placement of insurance coverage with insurance carriers, the establishment of
new business development and relationship management groups, and the building
of four CSBUs (New York City-World Trade Center, Los Angeles, Houston and
Glenview, Illinois). Successful pilot programs for the CSBUs were conducted
in the second quarter and the conversion of accounts started throughout the
summer. The CSBUs achieved significant improvement in client service levels
for converted accounts.

In third quarter 2001, a significant acceleration of process and file
conversions to the CSBUs was planned. These conversions fell behind schedule due
to unexpected challenges in handling higher volumes of transfers between field
operations and the CSBUs, and steps were being taken prior to September 11 to
improve the conversion process. The delays reduced cost savings and put pressure
on regional offices that had to maintain parallel systems to ensure quality
client service which resulted in duplicate costs. This also adversely affected
new business production in the quarter as attention was diverted from generating
new accounts to completing client conversions.

The most established CSBU was housed within the World Trade Center (WTC) - Aon's
largest U.S. retail brokerage branch. When the WTC was destroyed on September
11, client servicing was immediately rerouted to other CSBUs. This transfer was
more easily accomplished because of increased electronic document management
completed under the business transformation design. The World Trade Center CSBU
has now been relocated to midtown Manhattan along with a majority of the WTC
retail brokerage staff. We continue to maintain quality client service while
reestablishing our business operations in this interim space. The September 11
events, however, have exacerbated the delays in converting to the CSBUs.

A dedicated effort is currently underway to fully convert client servicing for
U.S. retail brokerage accounts to the four CSBUs by second quarter 2002 which
will involve unanticipated, one-time costs in fourth quarter 2001 and the first
half of 2002.

The business transformation in U.S. retail brokerage also involved changes in
job roles and responsibilities focusing on: new sales, relationship management,
syndication of business to insurance carriers, client service and product
specialization. Employees were advised of their new roles late in the first
quarter and in the second quarter and were still progressing in terms of
conducting their own new jobs, and learning how their new roles interrelated
with other employees' new responsibilities. Some of the complexities of the job
reorganization added to the CSBU conversion delay, which along with the
September 11 events, resulted in unsatisfactory financial performance in the
third quarter.

The Company does not anticipate any additional special charges for the business
transformation program beyond the $300 million already taken. Total costs
including both special charges and transition costs for the business
transformation are expected to exceed the upper range of the original total cost
estimate due to these additional transition costs.

The business transformation challenges are manageable and steps are already
being taken to significantly improve performance. As the conversion process
between the regional offices and

                                       7
<Page>

the CSBUs is completed and employees become more familiar with their new job
roles, the Company expects the creation of significant additional capacity to
produce new business that will further the goals of the business
transformation plan.

Michael D. O'Halleran, president and COO of Aon Corporation, stated, "We are
totally committed to the business transformation program. We undertook
industry-leading changes in our operating model designed to improve service for
our clients and create operating efficiencies. Implementation of certain steps
in U.S. retail brokerage have lagged our initial timeline and new account
generation and expenses have suffered in the near-term, but we have enormous
talent and resources in our organization and our long-term prospects are very
positive. I look forward to directly leading and reinvigorating our efforts."

IMPACT OF SEPTEMBER 11, 2001
Consolidated pretax charges related to the events of September 11 were $53
million, or $0.12 per share, and were recorded in third quarter 2001. The
charges were principally comprised of $45 million of insurance benefits, net of
approximately $147 million of reinsurance, provided under life insurance
policies issued by Aon's Combined Insurance Company subsidiaries for Aon
employees. As to approximately $90 million of such reinsurance recoverables,
issues have recently been raised by reinsurers and the Company is in discussions
regarding those issues. Charges also included extended medical benefits of $7
million provided to the families of deceased employees.

Aon is still in the process of presenting additional insurance claims for losses
related to the WTC to its insurers. The Company expects additional recoveries in
future periods from its insurance policies that cover the value of destroyed
assets and the continuing excess and extra costs related to business
interruption.

Aon has secured major temporary office space in midtown Manhattan to accommodate
the majority of the employees displaced by September 11 and has also relocated
employees to alternative NYC metropolitan offices. The vast majority of our
employees have returned to work and information technology systems and
applications, as well as telecommunications services for these employees, have
been provided.

"Given the magnitude of the loss of life and destruction at the World Trade
Center, we will never know the full impact of this tragedy," Ryan said. "We are
not looking back though - we are looking ahead. Our employees have exhibited
incredible strength, character and resolve to move forward and it is this
commitment that gives me great confidence in our future success."

"From a broader industry perspective, the terrorist attacks of September 11 have
placed insurance and risk management issues in the spotlight," Ryan also noted.
"The September 11 events have caused fundamental changes to the insurance
industry beyond the mere hardening of the market that was witnessed prior to
September 11. Aon is well-positioned as a leader in designing and delivering
solutions that help address the unique risk management, human capital and
insurance challenges our clients face in this new environment."

SPIN-OFF UPDATE AND PROPERTY AND CASUALTY INITIATIVE

                                       8
<Page>

In April 2001, the Company announced plans to spin-off its underwriting
operations to stockholders through a new company to be named Combined Specialty
Corporation. On October 12th, Aon announced plans to expand its underwriting
operations to include direct property and casualty insurance and reinsurance
policies to meet clients' growing demand for insurance coverage. These expanded
operations are intended to be part of the spin-off and will require the raising
of additional capital. A separate release to be issued later today will provide
additional information concerning Aon's strategy for property and casualty
underwriting.

The Company is currently involved in the customary review process with the IRS
for a favorable tax-free ruling for the planned spin-off. Customary SEC filings
will be made by the Company regarding the spin-off and will be sent to
stockholders. The spin-off is expected to be completed by Spring 2002 and
requires final Board approval.

"The shortage of capacity in the insurance market created by the events of
September 11 have led Aon to expand the types of underwriting that we will
support," stated Ryan.

FUTURE OUTLOOK
"Visibility into near-term financial results has been obscured by a number of
factors, both external and internal," said Ryan. "Our company was shaken by the
events of September 11, and we are completing important implementation steps for
our business transformation. The insurance industry is undergoing unprecedented
change and the need for our services has never been greater. In addition to
providing risk management expertise, we are working to deliver additional
underwriting capacity that will be included under our planned spin-off.
Simultaneously, we are witnessing a decline in global economies, volatile equity
markets and sinking interest rates."

"Most of our business units are performing well and dramatically increasing
premium rates are expected to have a positive effect on brokerage commissions
and fees. However, Aon's fourth quarter 2001 Corporate segment revenue will be
negatively impacted by the equity market decline. Lower interest rates will
pressure investment income and policy extensions may delay billings for some
annual renewals to 2002 due to insurance capacity constraints and stricter
underwriting. Implementation of the U.S. retail brokerage transformation will
continue and additional unplanned costs will be incurred. Start-up costs will
also be incurred to initiate the expansion of property and casualty
underwriting, but earned premium from this new P&C growth is not expected until
2002."

"For 2002, earnings visibility is challenging for many of the same reasons. We
believe, however, that we will benefit from increasing premium rates and the
completion during 2002 of our business transformation in U.S. retail brokerage,
which will give the Company sizable savings and increased capacity for new
account generation," Ryan said. "Assuming that the equity markets improve from
current levels and we achieve a mid-single digit return next year on our equity
portfolio, we believe that a double-digit increase in earnings per share from
$2.01 in 2000 is achievable in 2002, excluding the elimination of goodwill
amortization that will add another $0.36 per share to this increase."

                                       9
<Page>

Aon Corporation (www.aon.com) is a holding company that is comprised of a family
of insurance brokerage, consulting and insurance underwriting subsidiaries.
Aon's common stock is listed on the New York, Chicago, Frankfurt and London
stock exchanges.

This press release may contain certain statements relating to future results,
which are forward-looking statements as that term is defined in the Private
Securities Litigation Reform Act of 1995. These forward-looking statements are
subject to certain risks and uncertainties that could cause actual results to
differ materially from historical results or those anticipated, depending on a
variety of factors such as general economic conditions in different countries
around the world, fluctuations in global equity and fixed income markets,
changes in commercial property and casualty premium rates, the competitive
environment, the actual cost of resolution of contingent liabilities, the final
form of the business transformation plan, the ultimate cost and timing of the
implementation thereof, the actual cost savings and other benefits resulting
therefrom, whether the Company ultimately implements the proposed spin-off of
its underwriting operations, and the timing and terms associated therewith, and
events surrounding terrorists attacks of September 11, 2001, including the
timing and resolution of related insurance and reinsurance issues. Further
information concerning the Company and its business, including factors that
potentially could materially affect the Company's financial results are
contained in the Company's filings with the Securities and Exchange Commission.

                                         ###
Contact:    Sean P. O'Neill
            Vice President, Financial Relations
            312-381-3983


                                       10
<Page>

AON CORPORATION
CONSOLIDATED SUMMARY OF OPERATIONS
<Table>
<Caption>
                                                                                      THIRD QUARTER ENDED
                                                                             -------------------------------------
                                                                             SEPT. 30,     SEPT. 30,    PERCENT
(millions except per share data)                                               2001           2000      CHANGE
                                                                             ----------   -----------   ----------
                                                                                               
REVENUE
Brokerage commissions and fees                                               $   1,297     $  1,176     10       %
Premiums and other                                                               510          476       7
Investment income                                                                105          133       (21)
                                                                             ----------    ---------    ----------
TOTAL REVENUE                                                                    1,912        1,785     7
                                                                             ----------    ---------    ----------
EXPENSES
General expenses                                                                 1,384        1,208     15
Benefits to policyholders                                                        271          257       5
Interest expense                                                                 31           38        (18)
Amortization of intangible assets                                                40           38        5
                                                                             ----------    ---------    ----------
TOTAL EXPENSES                                                                   1,726        1,541     12
                                                                             ----------    ---------    ----------

INCOME BEFORE UNUSUAL & SPECIAL CHARGES                                          186          244       (24)
Unusual charges - World Trade Center                                             (53)         -         N/A
Special charges                                                                  -            -         -
                                                                             ----------    ---------    ----------
INCOME BEFORE INCOME TAX, MINORITY INTEREST AND ACCOUNTING CHANGE                133          244       (45)
Provision for income tax                                                         51           95        (46)
                                                                             ----------    ---------    ----------
INCOME BEFORE MINORITY INTEREST AND ACCOUNTING CHANGE                            82           149       (45)
Minority interest - 8.205% trust preferred capital securities                    (10)         (10)      -
                                                                             ----------    ---------    ----------
INCOME BEFORE ACCOUNTING CHANGE                                                  72           139       (48)
Cumulative effect of change in accounting principle, net of tax (1)              -            -         -
                                                                             ----------    ---------    ----------
NET INCOME                                                                   $   72        $  139       (48)     %
                                                                             ==========    =========    ==========
Preferred stock dividends                                                        (1)          (1)       -
                                                                             ----------    ---------    ----------
NET INCOME AVAILABLE FOR COMMON STOCKHOLDERS                                 $   71        $  138       (49)     %
                                                                             ==========    =========    ==========
NET INCOME PER SHARE:
Basic net income per share                                                   $   0 26      $  0 53      (51)     %
                                                                             ==========    =========    ==========

Dilutive net income per share:
Net income before unusual and special charges                                $   0.38      $  0.53      (28)     %
Unusual charges - World Trade Center                                             (0.12)       -         N/A
Special charges                                                                  -            -         -
Cumulative effect of change in accounting principle (1)                          -            -         -
                                                                             ----------    ---------    ----------
Dilutive net income per share                                                $   0.26      $  0.53      (51)     %
                                                                             ==========    =========    ==========
Dilutive average common and common equivalent shares outstanding                 275.4        262.8
                                                                             ==========    =========


                                                                                        NINE MONTHS ENDED
                                                                             -------------------------------------
                                                                             SEPT. 30,     SEPT. 30,    PERCENT
(millions except per share data)                                               2001           2000      CHANGE
                                                                             ----------    ----------   ----------
                                                                                               
REVENUE
Brokerage commissions and fees                                               $    3,925    $  3,584     10       %
Premiums and other                                                                1,510       1,435     5
Investment income                                                                 205         395       (48)
                                                                             ----------    ----------   ----------
TOTAL REVENUE                                                                     5,640       5,414     4
                                                                             ----------    ----------   ----------
EXPENSES
General expenses                                                                  4,085       3,741     9
Benefits to policyholders                                                         823         766       7
Interest expense                                                                  98          102       (4)
Amortization of intangible assets                                                 118         115       3
                                                                             ----------    ----------   ----------
TOTAL EXPENSES                                                                    5,124       4,724     8
                                                                             ----------    ----------   ----------

INCOME BEFORE UNUSUAL & SPECIAL CHARGES                                           516         690       (25)
Unusual charges - World Trade Center                                              (53)        -         N/A
Special charges                                                                   (218)       -         N/A
                                                                             ----------    ----------   ----------

INCOME BEFORE INCOME TAX, MINORITY INTEREST AND ACCOUNTING CHANGE                 245         690       (64)
Provision for income tax                                                          95          269       (65)
                                                                             ----------    ----------   ----------
INCOME BEFORE MINORITY INTEREST AND ACCOUNTING CHANGE                             150         421       (64)
Minority interest - 8.205% trust preferred capital securities                     (30)        (30)      -
                                                                             ----------    ----------   ----------
INCOME BEFORE ACCOUNTING CHANGE                                                   120         391       (69)
Cumulative effect of change in accounting principle, net of tax (1)               -           (7)       N/A
                                                                             ----------    ----------   ----------
NET INCOME                                                                   $    120      $  384       (69)     %
                                                                             ==========    ==========   ==========
Preferred stock dividends                                                         (2)         (2)       -
                                                                             ----------    ----------   ----------
NET INCOME AVAILABLE FOR COMMON STOCKHOLDERS                                 $    118      $  382       (69)     %
                                                                             ==========    ==========   ==========
NET INCOME PER SHARE:
Basic net income per share                                                   $    0.44     $  1.47      (70)     %
                                                                             ==========    ==========   ==========

Dilutive net income per share:
Net income before unusual and special charges                                $    1.05     $  1.49      (30)     %
Unusual charges - World Trade Center                                              (0.12)      -         N/A
Special charges                                                                   (0.49)      -         N/A
Cumulative effect of change in accounting principle (1)                           -           (0.03)    N/A
                                                                             ----------    ----------   ----------
Dilutive net income per share                                                $    0.44     $  1.46      (70)     %
                                                                             ==========    ==========   ==========
Dilutive average common and common equivalent shares outstanding                  271.0       261.7
                                                                             ==========    ==========
</Table>

(1) Adoption of SEC Staff Accounting Bulletin 101, effective January 1, 2000.

<Page>

AON CORPORATION
OPERATING SEGMENTS

<Table>
<Caption>
                                                                                       THIRD QUARTER ENDED
                                                                       ----------------------------------------------------
                                                                       SEPT. 30,           SEPT. 30,          PERCENT
(millions)                                                               2001                2000             CHANGE
                                                                       --------------      --------------     -------------
                                                                                                     
REVENUE
Insurance brokerage and other services (1)                             $        1,112      $   1,042                 7  %

Consulting (2)                                                                    232            182                27

Insurance underwriting                                                            565            536                 5
                                                                       --------------      --------------     -------------
TOTAL REVENUE                                                          $        1,909      $   1,760                 8  %
                                                                       ==============      ==============     =============
INCOME BEFORE INCOME TAX
Insurance brokerage and other services                                 $          153        $   183               (16) %

Consulting                                                                         29             26                12

Insurance underwriting                                                             80             81                (1)
                                                                       --------------      --------------     -------------

TOTAL INCOME BEFORE INCOME TAX EXCLUDING UNUSUAL AND SPECIAL CHARGES              262            290               (10)
World Trade Center charges                                                        (53)             -               N/A
Special charges                                                                     -              -               N/A
                                                                       --------------      --------------     -------------
TOTAL INCOME BEFORE INCOME TAX                                         $          209        $   290               (28) %
                                                                       ==============      ==============     =============

                                                                                     NINE MONTHS ENDED
                                                                       -----------------------------------------
                                                                       SEPT. 30,      SEPT. 30,      PERCENT
(millions)                                                               2001           2000         CHANGE
                                                                       -----------    ----------     -----------
                                                                                            
REVENUE
Insurance brokerage and other services (1)                             $    3,383     $   3,181          6 %

Consulting (2)                                                                673           538         25

Insurance underwriting                                                      1,680         1,618          4
                                                                       -----------    ----------     -----------
TOTAL REVENUE                                                          $    5,736     $   5,337          7 %
                                                                       ===========    ==========     ===========
INCOME BEFORE INCOME TAX
Insurance brokerage and other services                                 $      544     $     545         (0)%

Consulting                                                                     84            68         24

Insurance underwriting                                                        227           227          -
                                                                       -----------    ----------     -----------

TOTAL INCOME BEFORE INCOME TAX EXCLUDING UNUSUAL AND SPECIAL CHARGES          855           840          2
World Trade Center charges                                                    (53)            -         N/A
Special charges                                                              (218)            -         N/A
                                                                       -----------    ----------     -----------
TOTAL INCOME BEFORE INCOME TAX                                         $      584       $   840        (30)   %
                                                                       ===========    ==========     ===========
</Table>

(1) Includes investment income of $46 million and $47 million for the third
quarter ended September 30, 2001 and 2000, respectively, and $127 million and
$132 million for the nine months ended September 30, 2001 and 2000,
respectively.

(2) Includes investment income of $1 million and $2 million for the third
quarter ended September 30, 2001 and 2000, respectively, and $4 million for both
the nine months ended September 30, 2001 and 2000.

<Page>



<Page>

AON CORPORATION
CORPORATE AND OTHER

<Table>
<Caption>
                                                                                                THIRD QUARTER ENDED
                                                                                     ------------------------------------------
                                                                                     SEPT. 30,       SEPT. 30,      PERCENT
(millions)                                                                             2001            2000         CHANGE
                                                                                     ----------      ----------     -----------
                                                                                                           
CORPORATE AND OTHER REVENUE (1)                                                         $  3          $ 25             (88)%

NON OPERATING EXPENSES

   Amortization of goodwill                                                             $ 30          $ 29               3%

   Interest expense                                                                       31            38             (18)

   General expenses                                                                       18             4             350
                                                                                     ----------      ----------     -----------
   LOSS BEFORE INCOME TAX                                                               $(76)         $(46)            N/A%
                                                                                     ----------      ----------     -----------
                                                                                     ----------      ----------     -----------

<Caption>

                                                                                                 THIRD QUARTER ENDED
                                                                                     --------------------------------------------
                                                                                     SEPT. 30,       SEPT. 30,      PERCENT
(millions)                                                                             2001            2000         CHANGE
                                                                                     ----------      ----------     -------------
                                                                                                           
(1) COMPONENTS OF CORPORATE AND OTHER REVENUE
   Change in valuation on private limited partnership investments                         $ 7             $15            (53)%

   Income from marketable equity securities and other investments                           2               2              -
                                                                                     ----------      ----------     -------------

   CORPORATE AND OTHER REVENUE BEFORE INCOME (LOSS) ON DISPOSALS AND RELATED
   EXPENSES                                                                                 9              17            (47)

   Income (loss) on disposals and related expenses                                         (6)              8            N/A
                                                                                     ----------      ----------     -------------
   CORPORATE AND OTHER REVENUE                                                            $ 3             $25            (88)%
                                                                                     ----------      ----------     -------------
                                                                                     ----------      ----------     -------------


                                                                                                NINE MONTHS ENDED
                                                                                     ------------------------------------------
                                                                                     SEPT. 30,        SEPT. 30,       PERCENT
(millions)                                                                              2001            2000          CHANGE
                                                                                     ---------        ----------      ---------
                                                                                                             
CORPORATE AND OTHER REVENUE (1)                                                        $(96)            $  77            N/A%

NON OPERATING EXPENSES
   Amortization of goodwill                                                            $ 88             $  85              4%

   Interest expense                                                                      98               102            (4)

   General expenses                                                                      57                40             43
                                                                                     ---------        ----------      ---------
   LOSS BEFORE INCOME TAX                                                              (339)            $(150)            N/A%
                                                                                     ---------        ----------      ---------
                                                                                     ---------        ----------      ---------

                                                                                                NINE MONTHS ENDED
                                                                                     ------------------------------------------
                                                                                     SEPT. 30,        SEPT. 30,       PERCENT
(millions)                                                                              2001            2000          CHANGE
                                                                                     ------------     ------------    ---------
                                                                                                             
(1) COMPONENTS OF CORPORATE AND OTHER REVENUE
   Change in valuation on private limited partnership investments                         $(56)              $75           N/A%

   Income from marketable equity securities and other investments                            6                 6             -
                                                                                     ------------     ------------    ---------

   CORPORATE AND OTHER REVENUE BEFORE INCOME (LOSS) ON DISPOSALS AND RELATED EXPENSES      (50)               81           N/A

   Income (loss) on disposals and related expenses                                         (46)*              (4)          N/A
                                                                                     ------------     ------------    ---------
   CORPORATE AND OTHER REVENUE                                                            $(96)              $77           N/A%
                                                                                     ------------     ------------    ---------
                                                                                     ------------     ------------    ---------
</Table>

* Includes impairment writedowns of $29 million in first quarter 2001.