P/B Ratio (Price-to-Book Ratio) compares a stock’s market price to its book value—the net asset value on the company’s balance sheet. A P/B of 2 means you pay ₹2 for every ₹1 of book value. It’s particularly useful for valuing banks, financial companies, and asset-heavy businesses where book value is a meaningful measure of worth.
- Compares market price to accounting book value
- Below 1.0 may signal undervaluation (or problems)
- Most useful for banks and asset-heavy companies
How P/B Ratio Works
The formula relates price to net assets:
P/B Ratio = Stock Price ÷ Book Value Per Share
Book Value Per Share = (Total Assets - Total Liabilities) ÷ Shares Outstanding
Example:
Total Assets: ₹10,000 crore
Total Liabilities: ₹6,000 crore
Book Value: ₹4,000 crore
Shares: 100 crore
Book Value Per Share: ₹40
Stock Price: ₹80
P/B Ratio: 80 ÷ 40 = 2.0
You pay ₹2 for every ₹1 of net assets
Quick Reference: P/B Interpretation
| P/B Range | Meaning | Implication |
|---|---|---|
| < 1.0 | Below book value | Potential value or value trap |
| 1.0-2.0 | Near book value | Fair for asset-heavy businesses |
| 2.0-5.0 | Premium to book | Normal for quality companies |
| > 5.0 | Large premium | Asset-light or high-growth |
Example: P/B Ratio for Banks
Comparing PSU and Private Banks:
| Bank | Price | Book Value | P/B | ROE |
|---|---|---|---|---|
| SBI | ₹600 | ₹400 | 1.5 | 15% |
| HDFC Bank | ₹1,600 | ₹500 | 3.2 | 17% |
| Punjab National | ₹100 | ₹120 | 0.83 | 8% |
Analysis:
- PNB trades below book (P/B < 1)—market doesn’t trust asset quality
- HDFC Bank commands 3.2x book—premium for quality and growth
- SBI at 1.5x—moderate premium, decent quality
- Higher ROE typically commands higher P/B
P/B ratio compares stock price to book value per share. Below 1.0 means paying less than net assets—potentially cheap or troubled. Use P/B primarily for banks and asset-heavy companies where book value is meaningful.
Why P/B Matters
For Value Investing
Benjamin Graham famously looked for stocks trading below book value. Today, P/B < 1 may indicate deep value opportunities—or value traps.
For Bank Analysis
Banks are valued primarily on P/B because their assets (loans) are close to market value. A well-run bank trades at 2-3x book; struggling banks trade below book.
When P/E Fails
If earnings are negative or volatile, P/E ratio is useless. P/B works regardless of current profitability.
P/B Limitations
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Asset-light businesses – Software, consulting, and service companies have minimal book value. High P/B is normal, not expensive.
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Intangible assets – Brand value, patents, and customer relationships don’t appear on books. Book value understates true worth.
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Accounting variations – Different depreciation methods and asset valuations affect book value comparability.
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Historical cost – Assets on books may be worth more (real estate) or less (obsolete inventory) than stated.
Common Mistakes
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Using P/B for tech stocks – P/B is meaningless for asset-light businesses. Use P/E or P/S instead.
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Assuming low P/B = bargain – P/B below 1 often signals real problems. Investigate why market discounts assets.
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Ignoring ROE – High P/B is justified if company generates high returns on that book value.
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Cross-sector comparison – P/B of 3 is expensive for a steel company but cheap for a software company.
How JournalPlus Tracks P/B
JournalPlus lets you log P/B ratios for banking and financial sector trades, helping you track whether you’re buying quality banks at fair valuations.
