Prime cost is the combination of your food cost and your labor cost -- the two largest controllable expenses in any restaurant. If you add them together and divide by your total revenue, you get your prime cost percentage. That number, more than any other single metric, determines whether your restaurant has a future.
The industry benchmark is 60% or below for full-service restaurants and 55% or below for limited-service. If your prime cost is running above 65%, you are almost certainly losing money -- even if your POS system shows positive sales every night. The math does not care how busy you feel.
Why prime cost matters more than food cost alone
Most restaurant owners track food cost. Fewer track prime cost. That gap is expensive.
Here is why: food cost and labor cost are not independent variables. When you cut food cost by reducing portion sizes or switching to lower-quality ingredients, you often lose covers -- and labor cost as a percentage of revenue goes up because your staff is still there whether the dining room is full or not. When you cut labor by reducing staff, food quality suffers and you lose covers again. The two costs are linked, and optimizing one without watching the other is how operators end up with a food cost of 28% and a labor cost of 42% and wonder why they are still losing money.
The National Restaurant Association's 2026 State of the Industry report found that 42% of independent restaurant operators reported their business was not profitable in the prior year. In nearly every case, the root cause was a prime cost that had drifted above 65% without the owner noticing -- because they were watching food cost and labor cost separately, not together.
What drives prime cost above 60%
The most common culprits are not dramatic. They are slow leaks.
Food cost creeps up when invoices are not audited weekly, when portion control is inconsistent, when waste is not tracked, and when menu prices have not been updated to reflect ingredient cost increases. According to the U.S. Bureau of Labor Statistics, average food costs for restaurants are now more than 35% above pre-pandemic levels. A menu priced in 2021 is almost certainly underpriced today.
Labor cost creeps up when scheduling is done by habit rather than by projected covers, when overtime is not managed, and when the owner is on the floor doing jobs that should be done by lower-cost staff. The most expensive labor in most independent restaurants is the owner's time -- which is often untracked and therefore invisible in the numbers.
When both costs are drifting simultaneously, prime cost can move from 60% to 70% over six months without triggering any single obvious alarm. By the time the bank account makes the problem undeniable, the window for a clean fix has often closed.
How to calculate yours right now
Take your last four weeks of data. Add your total food cost (what you paid for ingredients, not what you sold) to your total labor cost (wages, payroll taxes, benefits). Divide that number by your total revenue for the same period. Multiply by 100. That is your prime cost percentage.
If it is above 65%, you have a problem that needs attention now, not next quarter. The Break-Even Calculator on this site will show you exactly what revenue you need to cover your fixed costs -- but if your prime cost is above 65%, you may need to fix the cost structure before the break-even math becomes achievable at all.
If you want a clear read on whether your prime cost is fixable or whether it reflects a deeper structural problem with the business, book a session with Rod. He has spent 40 years watching how this number behaves across different restaurant types, and he can tell you in one hour whether the path forward is a cost fix or a harder conversation.
Sources: National Restaurant Association -- 2026 State of the Industry | U.S. Bureau of Labor Statistics -- Food Away from Home CPI