Return on Equity (ROE)

What it is

Return on equity measures the profit a company generates for every pound of shareholders' equity invested in the business. If a company earns £200m of net profit and its shareholders' equity is £1bn, ROE is 20%. Shareholders are earning 20p for every pound of their capital employed in the business.

It's the financial equivalent of asking: if you invested £1 in this business, how much profit did you get back?

How to calculate it

Most analysts use average shareholders' equity — the midpoint between the start and end of the year — to avoid distortions from capital raised or returned during the period.

Why it's a quality metric

A company generating 25% ROE year after year has two possible explanations: either it has a genuinely superior business model — better products, stronger brands, more efficient operations — or it's using significant leverage to boost equity returns. Distinguishing between these is essential.

The DuPont decomposition breaks ROE into three components:

• Net margin (profit as % of revenue): how efficiently the business converts sales to profit
• Asset turnover (revenue ÷ total assets): how efficiently it uses its asset base
• Financial leverage (total assets ÷ equity): how much debt is amplifying returns

A software company with 30% net margin, reasonable asset turnover, and low leverage can achieve excellent ROE through genuine business quality. A retailer with 3% net margin but very high asset turnover (assets turn over many times a year) can also achieve good ROE. A bank with moderate margins but extremely high leverage (assets 15x equity) reports high ROE that is entirely a function of that leverage.

Understanding which lever is driving ROE prevents misinterpretation.

Sustainable ROE vs leveraged ROE

The critical question: is this ROE sustainable without excessive risk?

A company achieving 20% ROE with 0.3x debt/equity and 15% net margin is on solid ground. The same ROE achieved with 4.0x debt/equity and 3% net margin is fragile — a moderate revenue decline or margin compression could leave the business unable to service its debt, and the ROE will collapse or go negative.

This is why ROCE (Return on Capital Employed, which uses operating profit before interest and total capital rather than just equity) is sometimes preferred — it shows the return on the whole enterprise rather than just the equity component, and isn't flattered by leverage.

What's a good ROE?

For most industrial and consumer businesses, ROE consistently above 15% suggests a genuinely good business. Above 20% indicates a strong competitive position. Below 10% suggests either a challenging industry structure or capital misallocation.

UK sector averages vary significantly:

• Consumer staples: 20–35% (Unilever, Diageo)
• Technology: 20–50% (Sage, Kainos)
• Banks: typically target 10–15% as strategic returns
• Utilities: 8–12% (regulated, capital-intensive)
• Mining: highly cyclical, 5–30% through the cycle

The share buyback effect

Aggressive share buybacks reduce shareholders' equity (cash leaves the balance sheet, equity account shrinks). This mechanically raises ROE even if profits are unchanged. Diageo's ROE appears very high partly because decades of buybacks have reduced the book equity to a very small number relative to profits.

This is not necessarily a bad thing — returning excess capital is often excellent shareholder value creation — but it means ROE for mature companies with long buyback histories should be interpreted with this in mind.

Not financial advice. ROE analysis should always include the DuPont decomposition to understand the source of returns.