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Expense Ratio % is the percentage of expenses associated with acquiring, underwriting, and servicing premiums to net premium earned. It indicates the efficiency of the insurance company before considering its claims and investment gains or losses.
White Mountains Insurance Group's Expense Ratio % for the annual that ended in Dec. 2025 was 0.00%
, which is lower than
38.00% for the pervious year ended in Dec. 2016.
The historical rank and industry rank for White Mountains Insurance Group's Expense Ratio % or its related term are showing as below:
WTM's Expense Ratio % is not ranked *
in the Insurance industry.
Industry Median: * Ranked among companies with meaningful Expense Ratio % only.
White Mountains Insurance Group (NYSE:WTM) Expense Ratio % Explanation
Expense Ratio % is the percentage of expenses associated with acquiring, underwriting, and servicing premiums to net premium earned. It can be used to make comparisons between insurance companies as well as measure their performance. An expense ratio below 100% suggests that the premiums an insurance company earned or wrote are more than the expenses it paid to support those premiums.
However, we should keep in mind that the ratio does not indicate an ending profitability. The overall profit is also influenced by the claims, investment gains or losses and other income. The ratio can be combined with Claims Ratio % and Combined Ratio % to get an overall performance of an insurance company.
White Mountains Insurance Group Expense Ratio % Related Terms
White Mountains Insurance Group Expense Ratio % Historical Data
* 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.
White Mountains Insurance Group Expense Ratio % Chart
For the Insurance - Property & Casualty subindustry, White Mountains Insurance Group's Expense Ratio %, along with its competitors' market caps and Expense Ratio % 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.
White Mountains Insurance Group (NYSE:WTM) Expense Ratio % Calculation
Expense Ratio % is calculated as:
Expense Ratio %
=
Expenses of Acquiring, Underwriting and Servicing Premiums
/
Net Premium Earned
*
100%
* 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.
Frequently Asked Questions
What does a Expense Ratio % of 0.00% mean?
White Mountains Insurance Group (WTM) has a Expense Ratio % of 0.00% as of Sep. 2017. Expense Ratio is the percentage of expenses associated with acquiring, underwriting, and servicing premiums to net premium earned. View historical data on White Mountains Insurance Group and its competitors.
Is White Mountains Insurance Group's Expense Ratio % too high?
White Mountains Insurance Group's current Expense Ratio % is 0.00%. Overall, White Mountains Insurance Group has a GF Score™ of 75/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does White Mountains Insurance Group's Expense Ratio % compare to RLI and SIGI?
White Mountains Insurance Group's Expense Ratio % of 0.00% can be compared against companies in the Insurance industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Expense Ratio % for an Insurance company?
A good Expense Ratio % depends on the Insurance industry context. However, Expense Ratio % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Expense Ratio % mean?
A high Expense Ratio % can signal that a stock is expensive relative to its fundamentals. Expense Ratio is the percentage of expenses associated with acquiring, underwriting, and servicing premiums to net premium earned. View historical data on White Mountains Insurance Group and its competitors. White Mountains Insurance Group's current Expense Ratio % is 0.00%. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is White Mountains Insurance Group stock overvalued right now?
Based on GuruFocus' analysis, White Mountains Insurance Group (WTM) is currently considered Fairly Valued. The stock's GF Value™ is $2,385.35, compared to a current price of $2,208.05 — trading 7.4% below its estimated fair value. The current Expense Ratio % is 0.00%. White Mountains Insurance Group's overall GF Score™ is 75/100 with 3 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Expense Ratio % calculated?
Expense Ratio % is calculated from a company's financial statements. For White Mountains Insurance Group (WTM), the current Expense Ratio % is 0.00% as of Sep. 2017. 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 White Mountains Insurance Group (WTM) Overvalued in 2026?
Based on GuruFocus' analysis, White Mountains Insurance Group stock appears to be undervalued.
The current stock price of $2,208.05 is trading 7.4% below its estimated GF Value™ of $2,385.35.
GuruFocus considers White Mountains Insurance Group to be Fairly Valued.
Key valuation signals for WTM:
Expense Ratio %: 0.00%
GF Value™: $2,385.35 vs. price of $2,208.05 (7.4% below fair value)
No single metric tells the full story. See the WTM stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
White Mountains Insurance Group Business Description
White Mountains Insurance Group Ltd is engaged in the business of making opportunistic and value-oriented acquisitions of businesses and assets in the insurance, financial services, and related sectors, operating these businesses and assets through its subsidiaries and, if and when attractive exit valuations become available, disposing of these businesses and assets. The company conducts its business in five areas: property and casualty insurance and reinsurance, municipal bond reinsurance, capital solutions for asset and wealth management firms, property and casualty insurance distribution, and other operations. The company has four reportable segments: Ark/WM Outrigger, HG Global, Kudu and Distinguished.
75GF Score
Get the complete analysis for WTM
Expense Ratio % is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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