EX-23 8 exhibit23.htm EXHIBIT 23
Exhibit 23
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in the following Registration Statements:

Registration Statement |  |
Form |  | Number |  | Purpose
S-8 |  | 333-55773 |  | Pertaining to Aon's stock award plan, stock option plan, and employee stock purchase plan
S-4 |  | 333-168320 |  | Pertaining to the registration of 4,545,566 shares of common stock registered on Post Effective Amendment No. 1 related to the Amended and Restated Global Stock and Incentive Compensation Plan of Hewitt Associates, Inc.
S-8 |  | 333-103344 |  | Pertaining to the Aon Stock Incentive Plan
S-8 |  | 333-106584 |  | Pertaining to Aon's deferred compensation plan
S-8 |  | 333-145928 |  | Pertaining to the Aon Stock Incentive Plan
S-8 |  | 333-145930 |  | Pertaining to the registration of common stock underlying equity securities issued to Aon's president and chief executive officer
S-8 |  | 333-174788 |  | Pertaining to Aon's 2011 stock incentive plan and 2011 employee stock purchase plan
S-4 |  | 333-178991 |  | Pertaining to the registration of 355,110,708 Class A Ordinary Shares of Aon Global Limited, and in the related Proxy Statement / Prospectus of Aon Global and Aon Corporation contained therein
S-3 |  | 333-227514 |  | Pertaining to the registration of debt securities, guarantees, preference shares, Class A Ordinary Shares, Convertible Securities, share purchase contracts and share purchase units of Aon plc and debt securities and guarantees of Aon Corporation
S-8 |  | 333-184999 |  | Pertaining to Aon plc Company Share Save Plan
S-8 |  | 333-199759 |  | Pertaining to the registration of an additional 9,000,000 Class A Ordinary Shares to be issued pursuant to the Aon plc 2011 Incentive Plan
S-8 |  | 333-235296 |  | Pertaining to the registration of an additional 5,000,000 Class A Ordinary Shares to be issued pursuant to the Aon plc 2011 Incentive Plan

of our reports dated February 14, 2020, with respect to the consolidated financial statements of Aon plc and the effectiveness of internal control over financial reporting of Aon plc, included in this Annual Report (Form 10-K) of Aon plc for the year ended December 31, 2018.
/s/ ERNST & YOUNG LLP
Chicago, Illinois
February 14, 2020