Here is a conversation I have had with more business owners than I can count: they tell me their gross margin is 40 percent. I ask how they price their jobs. They say they mark up cost by 40 percent. I tell them they do not have a 40 percent gross margin. They do not believe me.

Let’s settle this once and for all — because this single misunderstanding is one of the most expensive pricing errors I see in the businesses I work with.

Why Gross Margin Is the Number That Actually Matters

Gross margin is what remains after you subtract cost of goods sold from revenue. It is the pool of money available to cover your overhead and generate a profit. If your gross margin is 40 percent and your overhead runs 30 percent of revenue, your net profit is 10 percent. The math is clean and direct. This is why gross margin is the number to build your pricing around. Not markup.

The Markup Trap

A product costs $1,000. You mark it up 40 percent. Selling price: $1,400. What is the actual gross margin?

Revenue $1,400 minus cost $1,000 equals gross profit $400. Gross margin percentage: $400 ÷ $1,400 = 28.6 percent. Not 40 percent. If the business needed 40 percent gross margin to cover overhead and turn a profit, it just fell more than 11 points short — on every single sale priced this way.

The Correct Calculation

If you know your cost and your required gross margin, the formula is:

Selling Price = Cost ÷ (1 − Desired GM%)

Using the same example: cost is $1,000, desired gross margin is 40 percent.

$1,000 ÷ (1 − 0.40) = $1,000 ÷ 0.60 = $1,667

Gross profit: $667. Gross margin: $667 ÷ $1,667 = 40 percent. Exactly what you needed.

The difference between pricing at $1,400 and $1,667 is $267 per unit. On 1,000 units a year, that is $267,000 of gross profit that evaporated — not because of bad sales, not because of rising costs, but because of a formula applied incorrectly.

The Rule

Always price to your required gross margin. Never to a markup percentage. If your pricing team, your sales team, or your estimators are using markup to set prices, stop. Rebuild the model around gross margin. The correction is simple. The impact is immediate.