Basis of Presentation

The accompanying Consolidated Financial Statements and Notes thereto have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). The Consolidated Financial Statements include the accounts of Aon plc and its controlled subsidiaries (“Aon” or the “Company”). Intercompany accounts and transactions have been eliminated. The Consolidated Financial Statements include, in the opinion of management, all adjustments (consisting of normal recurring adjustments and reclassifications) necessary to present fairly the Company’s consolidated financial position, results of operations and cash flows for all periods presented.

Discontinued Operations

On February 9, 2017, the Company entered into a Purchase Agreement (the “Purchase Agreement”) with Tempo Acquisition, LLC (the “Buyer”), an entity formed and controlled by affiliates of The Blackstone Group L.P. Pursuant to the Purchase Agreement, the Company sold its benefits administration and business process outsourcing business (the “Divested Business”) to the Buyer and certain designated purchasers that are direct or indirect subsidiaries of the Buyer (the “Transaction”). As a result, the Divested Business’s financial results are reflected in the Consolidated Statements of Income, Consolidated Statements of Financial Position, and Consolidated Statements of Cash Flows, retrospectively, as discontinued operations beginning in the first quarter of 2017. Additionally, all of the Notes to Consolidated Financial Statements have been retrospectively restated to only include the impacts of continuing operations, unless noted otherwise. The Transaction closed on May 1, 2017. Refer to Note 4 “Discontinued Operations” for additional information.

Reportable Segments

Beginning in the first quarter of 2017, the Company began operating as one segment that includes all of Aon’s continuing operations, which provides advice and solutions to clients focused on risk, retirement, and health through five revenue lines that make up the Company’s principal products and services. Refer to Note 17 “Segment Information” for additional information.

As a result of these initiatives, Aon made the following changes to its presentation of the Consolidated Statements of Income beginning in the first quarter of 2017:


•	Commissions, fees and other and Fiduciary investment income are now reported as one Total revenue line item; and


•	Other general expenses has been further broken out to provide greater clarity into charges related to Information technology, Premises, Depreciation of fixed assets, and Amortization and impairment of intangible assets.

Prior period comparable financial information has been reclassified to conform to this presentation.

The Company believes this presentation provides greater clarity into the risks and opportunities that management believes are important and allows users of the financial statements to assess the performance in the same way as the Chief Operating Decision Maker (the “CODM”).

Other

Beginning in the first quarter of 2017, the Company began presenting Shares issued - employee benefit plans and Shares issued - employee compensation as one line item on the Consolidated Statements of Shareholders’ Equity titled Shares issued - employee stock compensation plans.

Use of Estimates

The preparation of the accompanying Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of reserves and expenses. These estimates and assumptions are based on management’s best estimates and judgments. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. Management believes its estimates to be reasonable given the current facts available. Aon adjusts such estimates and assumptions when facts and circumstances dictate. Illiquid credit markets, volatile equity markets, and foreign currency exchange rate movements increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in estimates resulting from continuing changes in the economic environment would, if applicable, be reflected in the financial statements in future periods.