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AON 424B5: Secondary offering

Aon plc subsidiaries

Filed with the SEC on · accession 0001193125-26-392131

AON filed a 424B5 (prospectus (offering)) with the SEC on Sep 15, 2026. The final terms of an offering of shares or bonds. The stock moved -2.2% by the first close after the filing.

Summary of the filing

Aon plc subsidiaries issued $13.5 billion in senior notes across seven tranches to fund the USI acquisition and for general corporate purposes.

For details, click here →How to read a 424B5 →

Key details

Total offering amount$13.5B
5.350% Senior Notes due 2029$2.0B
5.625% Senior Notes due 2031$3.0B
5.800% Senior Notes due 2033$2.0B
5.950% Senior Notes due 2036$2.8B
6.100% Senior Notes due 2038$1.0B
6.450% Senior Notes due 2046$750.0M
6.450% Senior Notes due 2056$2.0B
GuarantorAon plc
IssuerAon North America, Inc.
IssuerAon Global Holdings plc
GuarantorAon Corporation
GuarantorAon Global Limited

How AON stock reacted

Close before

$311.54

Sep 14, 2026

First close after

-2.21%

$304.67

5 trading days

-6.65%

$290.82

Since filing

+7.47%

$334.81

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Frequently asked questions

What did AON file with the SEC on Sep 15, 2026?

AON filed a 424B5 (Secondary offering). Aon plc subsidiaries issued $13.5 billion in senior notes across seven tranches to fund the USI acquisition and for general corporate purposes.

What does a secondary offering mean for AON stock?

New shares dilute existing holders and are often sold at a discount to the market price.

How do I read a 424B5?

The final terms of an offering of shares or bonds. Look at price, number of shares and the discount to the market price. Large offerings dilute existing shareholders.

Why are SEC filings important?

Public companies must tell the SEC about anything that can change their value — results, leadership changes, big deals, new shares, bankruptcy. Filings are the official source, often before the news. A 424B5 (prospectus (offering)): The final terms of an offering of shares or bonds.

How did AON stock react to this filing?

AON closed at $311.54 before the filing and $304.67 on Sep 15, 2026 (-2.21%). Five trading days later: $290.82 (-6.65%).

Other AON SEC filings

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