Price-to-Book Ratio (P/B)
Key Takeaways
- P/B Ratio = Market Price per Share / Book Value per Share
- A P/B below 1.0 means the stock trades below the accounting value of its net assets
- Most useful for asset-heavy industries like banking, insurance, and real estate
- Less useful for technology and service companies with intangible-driven value
Definition
The price-to-book ratio (P/B) compares a company's stock market price to its book value per share. Book value represents shareholders' equity — the net asset value calculated as total assets minus total liabilities. A P/B of 1.0 means the stock is trading at exactly its accounting book value.
P/B is a key metric for value investors, who look for stocks trading below book value (P/B < 1.0) as potential bargains. Benjamin Graham, the father of value investing, used P/B as a core screening criterion. A stock trading below book value may indicate the market believes the company's assets are overvalued on the balance sheet, or it may represent a genuine buying opportunity.
P/B is most meaningful for companies whose value is closely tied to their tangible assets — banks, insurance companies, REITs, and manufacturing firms. For technology and service companies, whose value comes primarily from intangible assets like intellectual property and brand, P/B is less useful because those intangibles often do not appear on the balance sheet.
How It Works
P/B Ratio = Market Price per Share / Book Value per Share. Book Value per Share = Total Shareholders' Equity / Shares Outstanding. Alternatively, P/B = Market Capitalization / Total Shareholders' Equity.
P/B < 1.0: Stock trades below book value — may be undervalued or may reflect genuine impairment. P/B = 1.0-3.0: Common range for established companies. P/B > 3.0: Trading at significant premium to book — justified for high-ROE companies. Very high P/B (10x+): Typical for asset-light tech companies where book value is largely irrelevant.
The relationship between P/B and ROE is fundamental: P/B = ROE × P/E. Companies earning high returns on equity deserve to trade at premium P/B ratios because each dollar of book value generates more profit. A company with 25% ROE and 20x P/E should trade at 5.0x book value.
Example
JPMorgan Chase (JPM) trades at approximately 2.0x book value, reflecting its industry-leading ROE of ~17%. Competitor Citigroup (C) trades at approximately 0.6x book value, reflecting its lower ROE and market concerns about business complexity. For bank investors, this P/B comparison immediately reveals the market's view of each bank's asset quality and earnings power. A bank consistently trading below 1.0x book value suggests the market questions the value of its loan portfolio or management's ability to earn adequate returns.
Why It Matters
P/B is essential for industries where asset values on the balance sheet closely reflect economic reality. In banking, book value approximates the liquidation value of loans and investments. A bank trading below book value suggests the market fears loan losses or operational problems. For REITs, comparing price to net asset value (a modified P/B) is the standard valuation approach.
P/B also features prominently in academic research on the value premium — studies show that low P/B (value) stocks have historically outperformed high P/B (growth) stocks over long periods, though with cyclical variation.
Advantages
- Useful for asset-heavy industries where book value is meaningful
- Low P/B can identify undervalued stocks for value investors
- Provides a floor valuation based on accounting net worth
- Combined with ROE, reveals whether premium or discount is justified
Limitations
- Book value may not reflect market value of assets
- Meaningless for companies with negative book value
- Less relevant for asset-light businesses (tech, services)
- Intangible assets and goodwill can distort book value
Frequently Asked Questions
Related Terms
Browse more definitions in the financial terms glossary.