AonAON +1.71%88 Operating Margin % is 35.90% as of Mar. 2026, which is 59% above its 10-year median of 22.52. GuruFocus rates AON with a GF Score™ of 88/100 and a GF Value™ of $397.06 (Modestly Undervalued). The stock has 2 warning signs investors should review. Among 65 Insurance companies, Aon ranks better than 83.08% on this metric.
Operating Margin % is calculated as Operating Income divided by its Revenue. Aon's Operating Income for the
three
months ended in Mar. 2026 was $1,807 Mil. Aon's Revenue for the
three
months ended in Mar. 2026 was $5,034 Mil. Therefore, Aon's Operating Margin % for the quarter that ended in Mar. 2026 was 35.90%.
Good Sign:
Aon PLC operating margin is expanding. Margin expansion is usually a good sign.
The historical rank and industry rank for Aon's Operating Margin % or its related term are showing as below:
AON'
s Operating Margin % Range Over the Past 10 Years
Min: 9.79 Med: 22.52 Max: 29.4
Current: 28.28
AON's Operating Margin % is ranked better than 83.08% of 65
companies
in the Insurance industry
Industry Median: 11.8
vs AON: 28.28
Aon's 5-Year Average Operating Margin % Growth Rate was 5.20% per year.
Aon's Operating Income for the
three
months ended in Mar. 2026 was $1,807 Mil.
Its Operating Income for the trailing twelve months (TTM) ended in Mar. 2026 was $4,945 Mil.
Aon (NYSE:AON) Operating Margin % Explanation
Just like Gross Margin %, it is important to see a company maintains its operating margin over time. Among the same industry, a company with higher operating margin is more efficient in its operation. It is also more stable during industry slowdown or recessions. Peter Lynch prefers those with higher margins than those with lower margins.
Be Aware
Operating Margin % can be manipulated by adjusting the rate of depreciation, depletion and amortization (DDA).
If a company is facing competition, its Operating Margin % may decline. Often the Operating Margin % declines well before the company's Revenue or even profit decline. Therefore, Operating Margin % is a very important indicator of whether the company is facing problems.
For instance, by 2012, Nokia (NOK)'s problems were well known and its stock had lost more than 90% of its market value since 2007. But Nokias Operating Margin % had already been in decline since 2002, although its Earnings per Share (Diluted) were still rising. Investors who paid attention to Operating Margin % would have avoided this huge loss. The same can be said for Research-in-Motion (RIMM).
Therefore, Operating Margin % is a very important screening filter for GuruFocus. GuruFocus's Buffett-Munger screener requires that the profit margin is either consistent or expanding. The Model Portfolio of the Buffett-Munger screener has outperformed the market every year since inception in 2009.
Aon Operating Margin % Related Terms
Aon Operating Margin % Historical Data
* Premium members only.
The historical data trend for Aon's Operating Margin % can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
AON vs MRSH, AJG, WTW: Operating Margin % Comparison
For the Insurance Brokers subindustry, Aon's Operating Margin %, along with its competitors' market caps and Operating Margin % data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Aon Operating Margin % vs Insurance Industry
For the Insurance industry and Financial Services sector, Aon's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Aon's Operating Margin % falls into.
Operating Margin % - also known as operating income margin, operating profit margin and return on sales (ROS) - is the ratio of Operating Income divided by net sales or Revenue, usually presented in percent.
Aon's Operating Margin % for the fiscal year that ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Aon (AON) has a Operating Margin % of 35.90% as of Mar. 2026. Operating margin is the ratio of total operating income to net sales. View historical data on Aon and its competitors. This is 59% above median its historical median of 22.52. Over the past decade, Aon's Operating Margin % has ranged from 9.79 to 29.40. According to the industry distribution chart, Aon ranks #11 out of 65 companies in the Insurance industry, placing it in the top 16.9%.
Is Aon's Operating Margin % too high?
Aon's current Operating Margin % of 35.90% is 59% above median its 10-year median of 22.52. Over the past 10 years, this metric has ranged from a low of 9.79 to a high of 29.40. The Insurance industry median Operating Margin % is 11.80. Aon's value of 35.90% is 204.2% above this industry median. Based on the distribution chart, Aon ranks #11 out of 65 companies in the Insurance industry, which is in the top quartile — a strong position relative to peers. Overall, Aon has a GF Score™ of 88/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Aon's Operating Margin % compare to MRSH and AJG?
According to the Insurance industry distribution chart, Aon ranks #11 out of 65 companies for Operating Margin %. This places Aon in the top 17% of its industry — outperforming the majority of peers. The industry median Operating Margin % is 11.80. Aon's value of 35.90% is 204.2% above this benchmark. Historically, Aon's own Operating Margin % has ranged from 9.79 to 29.40 over the past decade. While the company's 10-year median is 22.52 vs. the industry median of 11.80, Aon has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Operating Margin % for an Insurance company?
The median Operating Margin % among Insurance companies is 11.80, based on 65 companies in the industry. Companies in the top quartile (top 25%) have a Operating Margin % significantly above this median, while those in the bottom quartile fall well below. However, Operating Margin % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Aon's current Operating Margin % of 35.90% is 204.2% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Operating Margin % mean?
A high Operating Margin % can signal that a stock is expensive relative to its fundamentals. Operating margin is the ratio of total operating income to net sales. View historical data on Aon and its competitors. For the Insurance industry, the median Operating Margin % is 11.80 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Aon's current Operating Margin % is 35.90%, which is 59% above median its own 10-year median of 22.52. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Aon stock overvalued right now?
Based on GuruFocus' analysis, Aon (AON) is currently considered Modestly Undervalued. The stock's GF Value™ is $397.06, compared to a current price of $326.23 — trading 17.8% below its estimated fair value. The current Operating Margin % is 35.90%, which is 59% above median its 10-year median of 22.52 and 204.2% above the Insurance industry median of 11.80. Aon's overall GF Score™ is 88/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Operating Margin % calculated?
Operating Margin % is calculated from a company's financial statements. For Aon (AON), the current Operating Margin % is 35.90% as of Mar. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Aon (AON) Overvalued in 2026?
Based on GuruFocus' analysis, Aon stock appears to be undervalued.
The current stock price of $326.23 is trading 17.8% below its estimated GF Value™ of $397.06.
GuruFocus considers Aon to be Modestly Undervalued.
Key valuation signals for AON:
Operating Margin %: 35.90% (59% above median its 10-year median of 22.52)
GF Value™: $397.06 vs. price of $326.23 (17.8% below fair value)
Industry Position: 204.2% above the Insurance median (#11 of 65)
No single metric tells the full story. See the AON stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Aon is a leading global provider of insurance and reinsurance brokerage and human resources solutions. Its operations are tilted toward its brokerage operations. Headquartered in London, Aon has about 60,000 employees and operations in over 120 countries.
88GF Score
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