Skip to main content

Valuing Insurance Companies: Underwriting Profit & Investing Income

Insurance companies are unique among financial institutions. They collect premiums from policyholders, invest those premiums in bonds and stocks, pay claims when losses occur, and pocket the difference. The challenge is that the "profit" from underwriting (premiums minus claims and expenses) may be negative—policies are sold at a loss—while the "profit" from investing the float is substantial. A company earning 2% underwriting margins but 5% returns on $100B float generates $5B in annual investing income. Valuation requires separating underwriting economics from investment returns.

Quick definition: Insurance valuation centers on combined ratio (claims + expenses / premiums), underwriting profit, and float arbitrage (return on float less cost of float). Book value and book value per share growth are primary metrics; multiples are applied to normalized earnings, distinguishing underwriting profit from investment gains.

Key Takeaways​

  • Combined Ratio below 100% indicates underwriting profit; above 100% indicates underwriting loss (money earned from investing, not underwriting)
  • Float (premiums held before claims are paid) is a source of capital that can be invested; float arbitrage is a key value driver
  • Loss Ratio (claims / premiums) is lower for property/casualty than for health insurance; reinsurance reduces loss exposure
  • Underwriting Profit Margin of 5–10% is strong; negative margins require investment returns to offset
  • Return on Equity (ROE) should exceed cost of equity (10%+); this justifies the business
  • Book Value Per Share (BVPS) growth is primary metric; multiples on book value (0.8–1.5×) vary by underwriting profitability and investing skill

Why Insurance Earnings Are Misleading​

An insurance company's reported earnings include two distinct streams:

  1. Underwriting Income: Premiums minus claims, commissions, and operational expenses
  2. Investment Income: Interest, dividends, and gains on the investment portfolio

These should be analyzed separately because they reflect different business economics.

Example (Property & Casualty Insurer):

  • Premiums collected = $10B
  • Claims paid = $7B
  • Expenses (commissions, admin, acquisition) = $2.5B
  • Underwriting income = $10B - $7B - $2.5B = $0.5B (5% underwriting margin)
  • Investment income (interest + dividends on $50B float) = $2B
  • Reported net income = $0.5B + $2B = $2.5B

Reported P/E based on $2.5B earnings is misleading if investment income is inflated by capital gains or declining rates. If rates rise and bond values fall, reported earnings collapse even if underwriting economics remain sound.

Intelligent investors separate underwriting earnings (true insurance business quality) from investment returns (market-driven, temporary).

Combined Ratio and Underwriting Profitability​

The Combined Ratio is the primary metric for insurance underwriting quality:

Combined Ratio = (Claims + Expenses) / Premiums

Or equivalently:

Combined Ratio = Loss Ratio + Expense Ratio

Where:

  • Loss Ratio = Claims / Premiums
  • Expense Ratio = Operating Expenses / Premiums (commissions, admin, overhead)

Interpretation:

  • Combined Ratio < 100%: Underwriting profit; the insurer makes money from underwriting
  • Combined Ratio = 100%: Break-even underwriting
  • Combined Ratio > 100%: Underwriting loss; the insurer loses money on premiums
  • Combined Ratio > 110%: Severe underwriting loss; expected for hardened insurance markets

By line of business:

  • Property & Casualty (auto, home, commercial): 95–105% combined ratio is normal; 90–95% indicates strong underwriting discipline
  • Health Insurance: 85–92% combined ratio (more stable claims patterns); above 95% signals adverse claims experience
  • Life Insurance: 75–88% combined ratio (lower claims volatility relative to premiums)
  • Reinsurance: 90–100% combined ratio (selective underwriting, catastrophe exposure)

A combined ratio above 100% does not mean the business is unprofitable—investment income offsets underwriting losses. But it signals underwriting discipline is lax, and profits depend on market conditions rather than core insurance operations.

Berkshire Hathaway example: GEICO auto insurer operates at combined ratios of 94–98%, indicating disciplined underwriting. Combined ratio above 100% would signal rate pressure or underwriting deterioration. The company's profitability is driven partly by float leverage (investment of premiums) but primarily by underwriting discipline.

Float and Float Arbitrage​

Float is the premiums held by the insurer before they are paid out as claims. Conceptually, the insurer has free use of that capital.

Float = Unearned Premiums + Loss Reserves

For a large insurer:

  • Unearned premiums: $30B (premiums received for policies not yet expired)
  • Loss reserves: $40B (claims incurred but not yet paid, pending settlement)
  • Total float: $70B

The insurer invests this $70B in bonds, stocks, and other assets, earning returns (let's say 4% = $2.8B annually).

Float Arbitrage is the difference between the return earned on float and the cost of that float:

Float Arbitrage = (Return on Float) - (Cost of Float)

The "cost of float" is the negative underwriting income (losses from operating the insurance business). If the insurer has a -2% underwriting margin (combined ratio 102%), the cost of float is -2%. If return on float is 4%, the arbitrage is 6%.

Example:

  • Float: $70B
  • Return on float: 4% = $2.8B
  • Underwriting loss (2% negative margin): -$1.4B
  • Float arbitrage: $2.8B - $1.4B = $1.4B

This is the essence of Berkshire Hathaway's strategy: accept underwriting losses to build float, then invest that float at high returns.

Loss Reserves and Reserve Adequacy​

Insurers must estimate their liability for claims that have been incurred but not yet paid (incurred but not reported, or IBNR). These are loss reserves.

Loss Reserves = Estimated liability for future claim payouts

Reserve adequacy is critical because:

  1. Insufficient reserves → The insurer underestimated liabilities; earnings will be negative when reserves are increased
  2. Excess reserves → The insurer overestimated liabilities; earnings improve when reserves are released

Reserve changes are a major source of earnings volatility. An insurer that releases reserves one year to boost earnings but must rebuild them later is not sustainable.

Intelligent assessment:

  • Stable reserve releases (same % of premium every year) indicate disciplined reserving
  • Increasing reserve releases (rising %) indicate the insurer is harvesting prior overestimation; this boosts earnings temporarily but is not repeatable
  • Increasing reserve additions (rising loss ratios on old accident years) indicate underestimation; a signal of claims inflation or underwriting deterioration

Reserve adequacy is assessed by comparing actual loss payouts to reserves incurred in prior years. If 2018 accident year had $5B in reserves but only $3.8B in claims paid through 2024, the reserves were excessive. If it had $5B in reserves but $5.2B in claims paid, reserves were inadequate.

Return on Equity and Cost of Float​

An insurer's Return on Equity (ROE) depends on underwriting profitability and investment returns:

ROE = (Underwriting Profit + Investment Income) / Shareholders' Equity

An insurer with 15% ROE is creating shareholder value if cost of equity is 10–11%. One with 8% ROE is destroying value if cost of equity is 10%.

Cost of Equity for an insurer varies by risk:

  • High-quality insurers (Berkshire, progressive auto): 10–11% cost of equity
  • Mid-tier regional insurers: 11–12% cost of equity
  • Reinsurers (catastrophe exposure): 12–13% cost of equity
  • Distressed or volatile insurers: 13–15% cost of equity

An insurer should target ROE above cost of equity plus 2–3% (to compensate for execution risk and market volatility). A "fair" insurer at 12% ROE with 10% cost of equity is generating a 200 bps excess return.

Book Value Per Share and P/B Multiples​

Book Value Per Share (BVPS) is the key valuation metric:

BVPS = Shareholders' Equity / Shares Outstanding

Insurers are valued using Price-to-Book (P/B) multiples:

P/B = Stock Price / Book Value Per Share

P/B multiple interpretation:

  • P/B < 0.9x: Discount to book; often indicates undervalued or distressed insurer
  • P/B = 0.9–1.1x: Near book; typical for weak underwriting
  • P/B = 1.1–1.4x: Premium to book; indicates strong underwriting or investment returns
  • P/B > 1.5x: High premium; indicates exceptional underwriting or growth expectations

The P/B multiple is justified by ROE relative to cost of equity. If an insurer has:

  • ROE = 12%
  • Cost of equity = 10%
  • Excess return = 2%

A P/B of 1.2× is approximately justified (excess return / cost of equity spread ≈ 2% / 10% = 20% premium).

Key Metrics for Underwriting Quality​

Loss Ratio (Claims / Premiums):

  • Indicates how much of each premium dollar is absorbed by claims
  • Lower is better; 75–85% is healthy for P&C
  • Above 90% indicates adverse claims experience

Expense Ratio (Operating Expenses / Premiums):

  • Indicates efficiency in underwriting and claims handling
  • Lower is better; 20–30% is typical
  • Above 35% signals inefficiency

Premium Growth Rate:

  • Indicates market share growth or rate increases
  • Organic growth (excluding acquisitions) signals competitive strength
  • Negative growth signals loss of market share

Catastrophe Loss Exposure:

  • Property & casualty insurers face concentration risk from major disasters
  • Large hurricanes or earthquakes create catastrophe losses that dwarf normal claims
  • Reinsurance transfers catastrophe risk but reduces underwriting profit

Persistency (Renewal Rates):

  • The percentage of customers who renew policies
  • Higher persistency (>95%) indicates pricing power and customer satisfaction
  • Lower persistency (<85%) indicates customers are switching to competitors

Integration into Insurance Valuation Models​

Separate Underwriting and Investment Returns:

  1. Calculate normalized underwriting earnings:

    • (Premiums - Expected Claims - Operating Expenses) / Shareholders' Equity
    • This reflects the core insurance business, normalized for the cycle

  2. Calculate normalized investment returns:

    • (Interest + Dividends - Realized Losses) / Float (or invested assets)
    • Normalize for unusual gains/losses and market cyclicity

  3. Apply multiples:

    • Underwriting ROE multiple (often 0.8–1.2× depending on quality)
    • Investment ROE multiple (often 1.0–1.2×)

  4. Book value growth model:

    • Project BVPS for 5–10 years
    • Assume underwriting ROE, investment ROE, and dividend payout
    • Apply terminal P/B multiple
    • Discount to present value at cost of equity

Example DCF for Book Value:

  • Current BVPS = $80
  • Projected ROE = 12% (underwriting 7%, investment 5%)
  • Payout ratio = 40% (retention = 60%)
  • Book value growth = ROE × Retention = 12% × 60% = 7.2%
  • Terminal growth = 3% (inflation)

Project BVPS:

  • Year 1: $80 × 1.072 = $85.76
  • Year 2: $85.76 × 1.072 = $91.93
  • ...
  • Year 5: $110.45
  • Terminal value (Year 5 at 1.3× P/B): $143.59
  • Discount to present at 11% cost of equity: ~$130

Intrinsic value: $130. If trading at $100, undervalued.

Real-World Examples​

Berkshire Hathaway (BRK.B): Combined ratio 95–98% (underwriting profit), float of $170B+ invested for 5–6% returns, ROE 15%+. Trades at 1.4–1.6× book, justified by superior underwriting and capital allocation. Underwriting discipline and investment skill are world-class.

Progressive (PGR): Auto insurer with combined ratio 95–100%, strong competitive position in direct/online channels. ROE 12–15%. P/B 1.1–1.3× reflects competitive advantages and disciplined underwriting. Premium growth has exceeded industry due to market share gains.

Allstate (ALL): Diversified insurer with combined ratio often 100–105% (underwriting breakeven or slight loss), compensated by $50B+ float invested at 4–5% returns. ROE 10–12%. P/B 0.9–1.1× reflects middle-of-pack underwriting. Dividend stable but growth limited.

Reinsurers (e.g., Everest Re, Axis Capital): Combined ratio 95–100%, ROE 11–13%, P/B 1.0–1.3×. Catastrophe exposure creates earning volatility; premium adequacy is critical. Post-major hurricanes, reserves are raised and multiples compress.

Common Mistakes​

1. Confusing underwriting profit with total earnings: An insurer with 105% combined ratio (underwriting loss of 5%) generating 10% ROE is profitable due to float returns, not underwriting skill. Do not assume the company is healthy; it is dependent on markets. Underwriting margins of 95–98% indicate true profitability.

2. Ignoring reserve adequacy trends: An insurer releasing reserves to boost earnings in one year but rebuilding them later is not sustainable. Track reserve releases as a % of premiums; rising releases signal eventual reversion.

3. Extrapolating investment income: Insurers often benefit from capital gains during bull markets and dividends when yields are high. Assume normalized investment returns (3–4% in down markets, 5–6% in normal times), not recent highs.

4. Underestimating catastrophe risk: P&C insurers hold their catastrophe exposure concentrations in specific geographies. A company concentrated in Florida hurricane zones faces outsized risk from Atlantic hurricane seasons. Stress-test for major cat events.

5. Using P/E instead of P/B: P/E is distorted by reserve changes and investment gains. P/B is cleaner; compare to historical P/B and peer multiples. A P/E of 10× may appear cheap when P/B of 1.5× indicates expensiveness.

6. Assuming persistent premium growth: New business growth and premium rate increases drive earnings; both are cyclical. In hardened markets, competitors raise prices faster, creating pricing pressure. Assume normalized premium growth (3–5%) unless company has demonstrated structural advantages.

Frequently Asked Questions​

Q: What's a good combined ratio? A: Below 100% indicates underwriting profit. For P&C: 95–98% is excellent, 100–102% is acceptable, above 105% is poor. For health: 88–92% is normal. Context matters: in hardened markets (high rates, selective underwriting), higher combined ratios are acceptable.

Q: How do I model catastrophe losses? A: Estimate the probability of major cat events (1-in-50-year hurricane, 1-in-100-year earthquake) and the expected impact on combined ratios. Reserve a portion of earnings for average annual cat losses. During actual cat events, earnings spikes and multiples compress. Over time, multiples should reflect normalized cat costs.

Q: Should I buy an insurer trading at 0.9× book? A: Only if underwriting quality is adequate and ROE justifies continued book value growth. A 0.9× discount often indicates poor underwriting (ROE < cost of equity) or market concern about reserve adequacy. If ROE is 12% and improving, 0.9× is a bargain. If ROE is 7% and deteriorating, 0.9× is a value trap.

Q: How does interest rates affect insurance valuations? A: Rising rates benefit P&C insurers through higher investment yields on the float and longer-duration return opportunities. But rates also increase competition (higher risk-free rates compete with insurance returns). Life insurers are negatively affected if liabilities are long-duration and rates rise. Property insurers are positively affected by higher float yields.

Q: What's the relationship between loss reserves and earnings quality? A: Consistent, predictable reserve releases indicate disciplined reserving. Volatile reserve releases signal uncertain liability estimation. An insurer that underestimates reserves must later increase them, depressing earnings. An insurer that overestimates can release them later, creating unsustainable earnings bumps. High-quality insurers have smooth, predictable reserve patterns.

Q: Can an insurer have high combined ratio but be valuable? A: Yes, if float is large and invested at high returns. Berkshire Hathaway's insurance operations have operated at 95–100% combined ratio with massive float ($170B+). The float arbitrage alone generates tens of billions annually. However, this requires scale and exceptional investment skill; a small insurer at 105% combined ratio is likely uneconomical.

  • Return on Equity and Cost of Capital: ../../chapter-07-leverage-and-capital-structure/01-debt-equity-and-valuation
  • Book Value and Tangible Book Value: ../../chapter-06-understanding-financial-statements/07-book-value-and-tangible-assets
  • Investment Portfolio and Income: ../../chapter-10-multiples-and-comparables/04-dividend-yield-and-payout-ratios
  • Leverage and Capital Adequacy: ../../chapter-07-leverage-and-capital-structure/02-leverage-and-default-risk

Summary​

Insurance company valuation requires separating underwriting profitability (combined ratio, loss ratio, expense ratio) from investment returns (float arbitrage). A combined ratio below 100% indicates underwriting profit; above 100% means the business is loss-making and dependent on float returns. Book value per share and price-to-book multiples are the primary metrics; use ROE relative to cost of equity to justify multiples. Reserve adequacy must be monitored; consistent reserve releases signal quality, while deteriorating reserves indicate hidden losses. Float is a source of capital arbitrage if invested wisely; Berkshire Hathaway exemplifies this strategy. Always stress-test valuations for catastrophe loss events, interest rate sensitivity, and reserve adequacy. A low P/B multiple on an insurer may indicate opportunity or a value trap depending on underwriting quality and ROE trajectory.

Next​

Coming Soon: Chapter 12 →