A moat is a durable advantage that keeps competitors from eroding a company’s profits.
▶ Watch: Economic Moat explained in 24 seconds
What it is
An economic moat is a structural feature that makes it hard for competitors to erode a company's profits. Common sources are intangible assets (brands, patents), switching costs, network effects, cost advantages, and efficient scale. The term was popularized by Warren Buffett and is used to judge whether high returns can last.
Why it matters
Returns on capital tend to fade toward the cost of capital over time as competition arrives. A wide moat slows that fade, so a moaty business can compound value far longer than its rivals. Paying up for a low-moat business is risky because its high margins may not survive.
How it's calculated
There is no single formula; a moat is assessed qualitatively from the source of advantage, then cross-checked quantitatively with persistently high return on invested capital (ROIC) above the cost of capital, stable or rising margins, and durable market share. The key test is durability, not just current profitability.
How Quintarthai uses it
Quinn's bull/bear case and the key-metrics grid on a company deep-analysis page highlight moat signals such as multi-year ROIC, margin stability, and market position.
Cross-border note. Canadian banks, railways, and pipelines often hold regulated or oligopoly moats (efficient scale), while many US moats come from software network effects and brands; compare in the company's home currency.
FAQ
Is a high profit margin proof of a moat?
No. A high margin today can come from a temporary lead. A moat is about whether competitors can take that margin away; durability and high returns on capital over many years are the real evidence.
What is the difference between a wide and a narrow moat?
It is a judgment about how long the advantage lasts. A wide moat is expected to protect excess returns for a long time (often described as 20 years or more), while a narrow moat protects them for a shorter, less certain period (often around 10 years).
Check your understanding
A company reports a very high profit margin this year. Why is that, by itself, not proof of an economic moat?
A moat is fundamentally about durability — whether high returns can survive competition for years — so a single high margin is not evidence on its own.