Gross margin vs operating margin vs net margin
"Margin" on its own is ambiguous. Gross margin, operating margin and net margin are all profit divided by sales, but each counts a different set of costs. Knowing which one someone means prevents a lot of bad comparisons.
The three definitions
Operating margin = operating income ÷ net sales, where operating income = gross profit − operating expenses
Net profit margin = net income ÷ net sales, where net income is after interest and income tax
The multi-step income statement described in OpenStax Principles of Accounting §6.6 reports these layers in order: net sales, cost of goods sold, gross margin (gross profit), operating expenses, income from operations, other revenue and expenses, then net income.
One illustrative income statement
A small retailer (invented numbers for the arithmetic only) has a year like this:
| Line | Amount | % of net sales |
|---|---|---|
| Net sales | $250,000 | 100% |
| Cost of goods sold | ($150,000) | 60% |
| Gross profit | $100,000 | 40.0% gross margin |
| Rent | ($24,000) | 9.6% |
| Salaries and wages | ($40,000) | 16.0% |
| Marketing | ($12,000) | 4.8% |
| Other operating expenses | ($6,000) | 2.4% |
| Operating income | $18,000 | 7.2% operating margin |
| Interest expense | ($3,000) | 1.2% |
| Income before tax | $15,000 | 6.0% |
| Income tax expense (illustrative) | ($3,150) | 1.26% |
| Net income | $11,850 | 4.74% net margin |
The same business has a 40% gross margin, a 7.2% operating margin and a 4.74% net margin. Each figure is correct; they simply include different costs.
What each margin tells you
| Measure | Answers | Moved mainly by |
|---|---|---|
| Gross margin | Is each sale priced well above its direct cost? | Price, purchase cost, product mix, discounts |
| Operating margin | Does the core business cover its overhead? | Rent, payroll, marketing, plus everything above |
| Net margin | What is left for the owners after everything? | Financing costs and tax, plus everything above |
Why a "good" gross margin can still lose money
Overhead does not shrink when gross margin is high. In the example, operating expenses are $82,000. If net sales fell 20% to $200,000 at the same 40% gross margin, gross profit would be $80,000, which is less than the overhead, so operating income would be −$2,000 even though every individual sale is still marked up 66.67% on cost. Volume questions like this are break-even questions; see the break-even calculator on our sibling site.
Where contribution margin fits
Contribution margin is a fourth, internal measure: sales minus all variable costs (including variable selling costs such as commissions), before any fixed costs. It does not appear on a standard multi-step statement but is the right number for break-even analysis. It is explained on ameticapital.com.
Computing the three margins from your own statement
- Start from net sales (after returns and discounts), not gross receipts.
- Gross margin: subtract cost of goods sold and divide by net sales.
- Operating margin: subtract all operating expenses from gross profit and divide by net sales.
- Net margin: subtract interest and income tax as well, then divide net income by net sales.
- Write down which costs you placed in cost of goods sold, so the next comparison uses the same split.
Comparison pitfalls
- Comparing your gross margin with someone else's net margin, or the reverse.
- Comparing gross margins when one business puts freight or payment fees in cost of goods sold and the other puts them in operating expenses.
- Using a single year: margins can swing with one-off costs.
- Treating any of these margins as cash; timing of payments and inventory purchases differs.
Sources for definitions
- OpenStax, Principles of Accounting Vol. 1 §6.6: Multi-step and simple income statements
- OpenStax, Managerial Accounting §3.1: Contribution margin
Definitions follow standard accounting usage as presented in the sources above. All dollar figures on this page are our own illustrative arithmetic.
Educational arithmetic only. Results do not set a suitable price or establish suitability for any lending, investment or business decision. See Use & limitations.