Net profit margin formula
Net profit margin is net income divided by net sales: the share of each sales dollar left after every cost of the business, including interest and income tax.[1]
Because it includes financing and tax, net margin can differ between two companies with identical operations: one with more debt pays more interest, and a pass-through business such as a sole proprietorship pays income tax at the owner level rather than on its own return.[2]
Gross vs operating vs net margin
Each margin stops at a different line of the income statement, so each answers a different question.
| Margin | Example | Profit it uses | Use it to judge |
|---|---|---|---|
| Gross margin | 40.0% | Revenue − COGS | Pricing and product cost |
| EBITDA margin | 15.3% | Before depreciation, interest and tax | Cash earnings of operations |
| Operating margin | 12.4% | EBIT: after all operating costs | How well the business runs |
| Pre-tax margin | 10.9% | After interest | Effect of debt |
| Net profit margin | 8.64% | After income tax | What owners keep |
The U.S. federal corporate income tax rate is a flat 21%, which is the default above; state taxes come on top, and owners of sole proprietorships, partnerships and S corporations should enter 0% and treat the result as pre-tax.[3]
Net margin by industry
Net margins in most industries are in single digits: in Aswath Damodaran's January 2026 data for U.S. public companies, the total market's net margin was 9.7%.[4]
| Industry | Firms | Gross | Operating | Net |
|---|---|---|---|---|
| Retail (General) | 23 | 33.2% | 6.8% | 5.6% |
| Retail (Grocery and Food) | 15 | 26.3% | 2.3% | 1.3% |
| Retail (Special Lines) | 94 | 35.3% | 7.7% | 5.2% |
| Restaurant/Dining | 64 | 32.2% | 15.8% | 9.4% |
| Apparel | 35 | 56.9% | 9.1% | 3.9% |
| Household Products | 110 | 51.0% | 18.6% | 11.7% |
| Business & Consumer Services | 155 | 33.4% | 12.3% | 7.0% |
| Software (System & Application) | 309 | 71.7% | 33.0% | 25.5% |
| Engineering/Construction | 48 | 15.5% | 6.5% | 5.9% |
| Trucking | 26 | 21.2% | 6.9% | 3.8% |
Public companies are larger than most small businesses and report under accounting rules that differ from a small firm's tax return, so treat these as direction, not as targets. The profit margin guide explains how to compare like with like.
Why net margin falls when sales rise
Net margin can drop in a growing business when operating costs climb faster than gross profit: new staff, a bigger warehouse or more advertising arrive before the extra sales do. Track the margins side by side. If gross margin holds while net margin falls, the problem is overhead, not pricing; use the break-even calculator to see how much sales must grow to cover a new fixed cost, and the gross margin calculator to check the product side. For a single item, the profit margin calculator gives the per-sale margin.
Frequently asked questions
How do you calculate net profit margin?
Divide net income (profit after every expense, interest and tax) by revenue and multiply by 100.
What is the difference between net margin and operating margin?
Operating margin stops at operating income, before interest and income tax. Net margin subtracts those too, so it is lower for a business that borrows or pays tax.
What is a good net profit margin?
It varies by industry. Grocery and other high-volume retailers often run on very thin net margins, while software firms can earn far more; compare with businesses in your own industry.
Can net profit margin be negative?
Yes. A negative net margin means the business lost money in the period after all costs.
Should I include the owner's pay?
For a fair comparison, include a market salary for the work the owner does as an operating expense. Otherwise a small business can look more profitable than it is.