As with many statistics, there's no single agreed-upon profit margin for the restaurant industry; conclusions (or educated guesses) vary from source to source. What's clear though and is widely agreed upon, when you look at various estimates for restaurants of every kind, from fast food to fine dining, is that profits in the restaurant industry are unusually thin.

What's a Profit Margin?

There are two profit margins widely used by accounting professionals: gross profit margin and net profit margin. Confusingly, some restaurant journalists write about profit margins without specifying which. Worse, when you read these articles carefully, you see that some use "profit margin" to refer to the gross profit margin and some use the same phrase to refer to net profit margin. There's a huge difference!

Gross Profit Margin

Gross profit, is what is left after you deduct the direct costs of goods sold – such as food costs and labor costs directly associated with preparation and serving. It's a useful statistic for professionals evaluating a restaurant's efficiency and profitability, but it's not at all the same thing as net profit – which includes all costs – among them are administrative expenses, building costs, taxes and interest. Net profit is what you put in your pocket.

Difference Between Gross Profit Margin and Net Profit Margin

Gross profit margin equals the revenue minus the cost of goods sold divided by revenue. Net profit margin equals revenue minus all costs, direct and indirect, divided by revenue.

When you want to know whether a restaurant is likely to succeed or go under, the best first place to look is at its net profit margin. If the net profit margin is 10 percent – this means that out of every dollar the customer spends – the restaurant pays 90 cents for all expenses, and retains ten cents in profit – which, incidentally, isn't at all bad. The average net profit margin for all S&P 500 companies is a little over 8 percent.

Fast Food Margins

The range of net margins in the fast food industry are quite wide. A few chains, especially McDonald's, have very healthy net margins. In 2017 , the average net profit margin for all McDonald's restaurants was over 22 percent. Among all franchises, however, net margins are drastically lower.

In 2012, for example, when McDonald's had a net profit margin of just under 20 percent; Burger King's net margin was less than a third of that and another big chain; Wendy's, had a scary thin 0.3 percent. This is very bad, but the fast food industry average for 2012 was only somewhat better, at 2.4 percent, a very thin margin that leaves little room for error.

Fast Casual and Casual

Casual dining, as it used to be called, is now commonly divided into two categories: fast casual and casual, sometimes called "family style."

Fast Casual restaurants include Chipotle, Shake Shack and similar chains where you order at the counter, sometimes having the food brought to the table, sometimes carrying at least part of your meal to the table yourself. It's often said that fast casual restaurants are distinguished from fast food chains by their healthier menus, but that may be more an aspiration than an actual difference.

In 2013, the fast casual segment of the restaurant industry had an average net profit margin of 6 percent. Overall, the fast-casual and casual segments together also averaged 6 percent net profit margins. To put this in context, this is a little more than 2 percent worse than the average of all S&P 500 companies, but nearly three times better than the fast food segment.

Full-Service Margins

Full-service restaurants are basically what's left after you subtract fast food, fast casual and casual restaurants. This market segment includes fine-dining restaurants, but it also includes less elegant places where, as in the fine dining segment of the industry, you're ushered to a table and handed a menu. The difference between fine-dining and other full-service restaurants isn't that the approaches are entirely different – both are "full-service" – but in the degree of refinement and, yes, how much it costs. The Houston's restaurant chain is probably right at about the dividing line between "full-service" and "fine-dining.