Share count
3Mpeak FY2016
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WTM, White Mountains Insurance Group Ltd.
Insurance — Property & Casualty financial
White Mountains Insurance Group Ltd. is an exempted Bermuda limited liability company whose principal businesses are conducted through its subsidiaries and affiliates.
As of December 31, 2025, White Mountains conducted its business primarily in five areas: property and casualty insurance and reinsurance, municipal bond guarantee reinsurance, capital solutions for asset and wealth management firms, specialty insurance distribution and other operations.
White Mountains provides capital solutions for asset and wealth management firms through its subsidiary Kudu Investment Management, LLC and its subsidiaries (collectively, "Kudu").
The business
What it sells, where the money comes from, the kind of company it is.
Revenue · FY2025
$3.7B
+66.8% YoY · 33% 5-yr CAGR
Vital signs · TTM, with 5-yr average
Revenue $518M −10.4% vs yr-ago qtr
Net income ($26M) yr-ago $63M
Net margin −5.1% yr-ago 10.9%
The business in brief
read the 10-K →What this business is and what moves its needle, from its own SEC filings.
- What moves the needle
- Underwriting discipline and the float. What decides it: whether the combined ratio stays below 100% so the policies make money on their own, how large the float is against equity, and what that float earns once it is invested. On its own account, the filing leans hardest on pricing power & competition, set against the numbers in what the filing emphasizes, below.
- Is it a good business?
- It runs an underwriting loss, about a 138% combined ratio, and must earn the difference back on the float. Book value per share, the measure Berkshire is judged on, has compounded about 13% a year across the record. The float runs about 0.2× equity, the leverage that magnifies both the underwriting and the investing. Whether the discipline holds through a soft market, and how the float is invested, are what the 10-K decides.
Every line is arithmetic on the company's filings, shown in full in the sections below.
The record
Ten years of arithmetic, read across the cycle.
The record, 2016–2025
realized figures from each filing · older years to the left| 2016’16 | 2017’17 | 2018’18 | 2019’19 | 2020’20 | 2021’21 | 2022’22 | 2023’23 | 2024’24 | 2025’25 | TTMTTMMar 2026 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Income statement | |||||||||||
| $158M | $374M | $401M | $893M | $896M | $747M | $1.2B | $2.2B | $2.2B | $3.7B | $3.7B | RevenueRevenue |
| $13M | $10M | $14M | $16M | $23M | $664M | $1.1B | $1.4B | $1.7B | $1.8B | $1.8B | Premiums earnedPremiums |
| $32M | $56M | $59M | $80M | $131M | $83M | $124M | $194M | $227M | $248M | $260M | Investment incomeInv. inc. |
| $402M | $627M | ($141M) | $415M | $709M | ($275M) | $793M | $509M | $230M | $1.1B | $1.0B | Net incomeNet inc. |
| -9% | -1% | — | 7% | -2% | — | 5% | -3% | 12% | 10% | 10% | Effective tax rateTax rate |
| Cash flow & returns | |||||||||||
| ($155M) | $95M | ($31M) | ($121M) | ($61M) | $39M | $365M | $404M | $587M | $551M | $621M | Operating cash flowOp. cash |
| — | — | — | — | — | ≈ 134% | ≈ 121% | ≈ 111% | ≈ 114% | ≈ 135% | ≈ 138% | Combined ratioCombined |
| 11% | 18% | -5% | 13% | 18% | -8% | 21% | 12% | 5% | 20% | 19% | Return on equityROE |
| 11% | 18% | −5% | 13% | 18% | −8% | 21% | 12% | 5% | 20% | 19% | Retained to equityRetained/eq |
| Balance sheet | |||||||||||
| $6.5B | $3.7B | $3.4B | $4.0B | $4.8B | $7.0B | $7.4B | $8.4B | $9.9B | $12.3B | $13.2B | Total assetsAssets |
| $367M | $97M | $110M | $161M | $85M | $148M | $255M | $122M | $266M | $186M | $924M | Cash & investmentsCash+inv |
| $3.6B | $3.5B | $2.8B | $3.3B | $3.9B | $3.5B | $3.7B | $4.2B | $4.5B | $5.4B | $5.4B | Shareholders’ equityEquity |
| Per share | |||||||||||
| 5.0M | 4.2M | 3.3M | 3.1M | 3.1M | 3.0M | 2.8M | 2.5M | 2.5M | 2.5M | 2.4M | Shares out (diluted)Shares |
| $81.12 | $147.94 | $-42.25 | $131.96 | $229.99 | $-90.52 | $280.52 | $201.48 | $90.99 | $436.57 | $427.12 | EPS (diluted)EPS |
| $1.09 | $1.09 | $1.14 | $1.02 | $1.04 | $1.02 | $1.06 | $1.03 | $0.99 | $1.03 | $0.98 | Dividends / shareDiv/sh |
| $723.30 | $823.80 | $850.62 | $1038.33 | $1267.61 | $1166.18 | $1325.77 | $1677.88 | $1770.67 | $2140.79 | $2195.69 | Book value / shareBVPS |
Per-share growththe realized rate an owner's share compounded
| 9-yr | 5-yr | |
|---|---|---|
| Revenue / share | +53.1%/yr | +38.4%/yr |
| EPS | +20.6%/yr | +13.7%/yr |
| Dividends / share | −0.7%/yr | −0.2%/yr |
| Book value / share | +12.8%/yr | +11.0%/yr |
The record, charted
FY2016–2025Each measure over its full record; the current point and the worst year marked.
Revenue
$3.7Blow FY2016
Quality & stewardship
Returns, the balance sheet, capital allocation, and pay.
Owner’s Scorecard
FY2025 10-K · source on SEC EDGAR →
Is it a good business?
- Combined ratio ≈ 135%Underwriting lossTotal benefits, losses and expenses $2.4B ÷ premiums earned $1.8BIndustry peers: median 100%
What this means
The heart of a property-casualty insurer: claims and costs as a share of premiums. Below 100% means it is paid to hold the float, the gold standard; above 100% means it loses money on the policies and must make it back on investments. Approximate here, taken from the filer's total benefits, losses and expenses over premiums, so it can sit a point or two off the company's headline figure; a number held below 100% across cycles is the mark of a disciplined underwriter, the rarest thing in the business.
- Return on equity 20%StrongNet income $1.1B ÷ equity $5.4BIndustry peers: median 10%
What this means
What it earns on shareholders' capital, the underwriting result plus what the float earns invested. Durably above the ~10% cost of equity is what compounds book value.
The float
- Float (reserves) $1.4B0.3× equityLoss and claim reserves $1.4B, 0.3× equity
What this means
Money held against future claims and invested in the meantime. Buffett's insight was that good underwriting makes this float cost less than nothing, a pool of other people's money the owners earn on. Measured here from loss and claim reserves only; it excludes unearned premiums and funds held, so the true float is somewhat larger than shown. The larger it is against equity, the more that leverage works, for better or worse.
- Investment income $248Mearned on investmentsNet investment income $248M
What this means
What the float and capital earned this year. This is the second engine: an insurer that breaks even on underwriting still wins if the float is large and invested well.
Does AI threaten the moat?
Low contestabilityThe moat is physical, regulated or balance-sheet-funded, the kind AI cuts costs within but does not contest.
AI is unlikely to contest a moat that is physical, regulated or balance-sheet-funded; here it reads more as a cost tool than a threat.
Read from the filing's own risk factors, paired with the industry's structure under its SIC code; the durability is read above, the price below.
All figures as filed; the source filing is linked above.
Management, ownership & pay
read the proxy →From the proxy: how much of the business the people running it own, and how they are paid, beside what the business earned for its owners in the same years.
| Fiscal year | Chief executive | Pay, as filed | “Actually paid” | Net income |
|---|---|---|---|---|
| 2021 | Mr. Rountree | $7.2M | $4.6M | ($275M) |
| 2022 | Mr. Rountree | $7.2M | $23.1M | $793M |
| 2023 | Mr. Rountree | $7.6M | $11.7M | $509M |
| 2024 | Mr. Rountree | $7.4M | $14.1M | $230M |
| 2025 | Mr. Rountree | $8.1M | $16.3M | $1.1B |
Both pay figures are the company’s own, from the pay-versus-performance table its proxy statement files. “As filed” is the Summary Compensation Table total: salary, bonus, and equity awards at their value on the day of grant. “Actually paid” is the SEC’s prescribed recalculation, which re-marks those equity awards to what they became as they vested; it can swing far above or below the filed figure in either direction, and negative years occur. Net income is the whole business's, as filed, for the same fiscal years.
- CEO pay ratio69:1
What the chief earns for every dollar the median employee makes, per the 2026 proxy. A high ratio alone settles nothing; some businesses are genuinely top-heavy in scarce skill. A runaway figure is where Buffett starts asking whether the board is doing its job.
- Stock-based compensation$19M
The slice of the business handed to employees in shares this year, 0% of revenue, equal to 1% of operating profit. Buffett's oldest accounting fight: this is compensation, compensation is an expense, real whether or not the headline earnings admit it. One trap: the cash-flow statement adds SBC back, so the operating cash, and the owner earnings drawn from it, are flattered by exactly this amount; counted as the cost it is, what an owner keeps is lower.
Peers, Insurance — Property & Casualty
The same industry, side by side on the underwriting lens. Each figure is a through-cycle median, so a peak or trough year can’t distort it; the group median at the foot is the line to read each against.
| Company | Revenue | Combined ratio | Loss ratio | ROE |
|---|---|---|---|---|
| THGHanover Insurance Group | $6.6B | 99% | 64% | 12% |
| AXSAxis Capital Holdings Limited | $6.6B | 101% | 66% | 6% |
| MCYMercury General | $6.0B | 100% | 76% | 10% |
| SIGISelective Insurance | $5.3B | 97% | 61% | 10% |
| KMPBKemper Corporation | $4.8B | — | 78% | 6% |
| WTMWhite Mountains Insurance Group Ltd. | $3.7B | 121% | — | 12% |
| SPNTSiriusPoint Ltd. | $3.2B | 111% | 67% | 10% |
| HGHamilton Insurance Group Ltd. Class B | $2.9B | 100% | — | 14% |
| Group median | — | 100% | — | 10% |
The price
What a price has to assume.
What the price implies
price / tangible bookAn insurer is worth a multiple of its tangible book value, and the multiple it deserves is set by the return it earns on that book. Type today’s price; we show what you would be paying against what White Mountains Insurance Group Ltd.’s record justifies.
$
The assumptions
Tangible book / share, delivered12%/yr’20→’25
The justified multiple is (return on tangible equity − growth) ÷ (cost of equity − growth). An insurer earning exactly its cost of equity is worth about one times tangible book; the premium above that prices each point of durable excess return. A higher cost of equity lowers the justified multiple for an insurer.
Enter a price above to run it.
Price / tangible book—
Justified by the return—
Normalized return on tangible equity15%
Price / book—
Earnings yield—
P/E (3-yr avg ’23–’25)—
Graham’s price gate—
Graham applied the same standards to financial enterprises (Intelligent Investor ch.14): the 15× multiple cap on averaged earnings, and P/E times price-to-book at most 22.5. The gate marks the bargain-hunter’s floor, not a verdict.
A dated snapshot of the price you typed, the assumptions you set, and what the page showed for them. A snapshot is never edited after it is saved. Your notebook is yours alone — the commitment states what is stored and what we will never do.
Tangible book $4.4B on 2M shares, a 15% normalized return on it. The dials set the multiple such a return would justify; your price sets the multiple you are paying. It assumes the insurer keeps earning that return; an underwriting cycle, a reserve shortfall or a bad year on the float changes it, which is what the record and the 10-K are for.
Cite: Owner Scorecard, "White Mountains Insurance Group Ltd. (WTM), the owner's record," https://ownerscorecard.com/c/WTM, data as of 2026-07-09.
Manual order: ← WTI its page in the Manual WTRG →
Industry order: ← WRB the Insurance — Property & Casualty chapter