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                             December 23, 2022

       Christa Davies
       Chief Financial Officer
       Aon plc
       The Metropolitan Building
       James Joyce Street
       Dublin 1, Ireland D01 K0Y8

                                                        Re: Aon plc
                                                            Form 10-K for the
Fiscal Year Ended December 31, 2021
                                                            Filed February 18,
2022
                                                            Form 10-Q for the
Quarterly Period Ended September 30, 2022
                                                            Filed October 28,
2022
                                                            File No. 001-07933

       Dear Christa Davies:

              We have limited our review of your filing to the financial
statements and related
       disclosures and have the following comments. In some of our comments, we
may ask you to
       provide us with information so we may better understand your disclosure.

              Please respond to these comments within ten business days by
providing the requested
       information or advise us as soon as possible when you will respond. If
you do not believe our
       comments apply to your facts and circumstances, please tell us why in
your response.

                                                        After reviewing your
response to these comments, we may have additional comments.

       Form 10-K for the Fiscal Year Ended December 31, 2021

       Notes to Consolidated Financial Statements
       Note 1. Basis of Presentation
       Revision of Previously Issued Financial Statements, page 59

   1.                                                   We note your disclosure
that you identified and corrected a presentation error related to
                                                        funds held on behalf of
clients in the Consolidated Statements of Cash Flows. Please
                                                        address the items
below.
                                                            Provide us with a
full and detailed description of the error, including, but not limited
                                                            to, a discussion of
who identified the error, when, and how, and whether it was the
                                                            result of any
control deficiency.
                                                            In your response to
the above bullet, ensure you include a thorough discussion and
 Christa Davies
Aon plc
December 23, 2022
Page 2
              description of the control deficiency to the extent one was
identified, the Company's
              evaluation of whether it was a control deficiency, significant
deficiency, or material
              weakness, and any remediation plans. To the extent the Company
concluded there
              was not a control deficiency, tell us why.
                Provide us with your assessment of materiality supporting your
conclusion that it was
              immaterial. Ensure that your response thoroughly addresses both
qualitative and
              quantitative factors as well as an objective assessment of
materiality from the
              perspective of a reasonable investor, including your
consideration of guidance in
              ASC 250, SAB 99, and management   s assessment of the design and
effectiveness of
              internal controls over financial reporting.
                Tell us how far you believe the errors go back and whether you
quantified the impact
              on periods prior to 2019.
Form 10-Q for the Quarterly Period Ended September 30, 2022

Management's Discussion and Analysis of Financial Condition and Results of
Operations
Revenue, page 31

2.       We note your disclosure on page 32 regarding AUM-based delegated
investment
         management revenue. In future filings, please enhance your disclosures
to more fully
         explain AUM movements impacting your revenues, such as quantification
of related
         AUM size trends, explanation of AUM-based fee arrangements, and what
is driving those
         changes period-over-period. In addition, clarify whether you hold any
related assets under
         management and, if so, quantify this and explain your responsibilities
related to them.
       In closing, we remind you that the company and its management are
responsible for the
accuracy and adequacy of their disclosures, notwithstanding any review,
comments, action or
absence of action by the staff.

       You may contact Cara Lubit at 202-551-5909 or Robert Klein at
202-551-3847 with any
questions.



FirstName LastNameChrista Davies                               Sincerely,
Comapany NameAon plc
                                                               Division of
Corporation Finance
December 23, 2022 Page 2                                       Office of
Finance
FirstName LastName