Understanding Prime Cost — The Number That Predicts Survival.

What is prime cost?

Prime cost is your total food and beverage cost plus your total labor cost, added together and expressed as a percentage of sales. That’s it — it’s not a new number, it’s two numbers you probably already track, combined into the one number that actually determines whether the restaurant makes money.

Prime Cost % = (Food & Beverage COGS + Total Labor Cost) ÷ Total Sales. Everything else on the P&L — rent, insurance, utilities, marketing — is largely fixed or slow-moving. Prime cost is the one category you can actually manage week to week, and it typically eats 55–70 cents of every sales dollar. There isn’t much room left over after that for anything to go wrong.

Why prime cost matters more than food cost alone

Food cost tells you half a story, and it’s easy to game the other half without meaning to. Cut food cost by switching to a cheaper protein, and if that means slower plate times and more prep labor, you may have just traded a food cost win for a labor cost loss — net prime cost unchanged, or worse. The reverse happens constantly too: a manager cuts labor hours to hit a scheduling target, service slows down, and comped or wasted plates push food cost right back up.

Prime cost catches the trade-off that food cost alone can’t see. It’s why almost every restaurant consultant, franchise operator, and lender who actually knows the industry asks for this number first — not food cost, not labor cost, prime cost.

What’s a healthy prime cost?

• Quick-service / limited-service: roughly 55–60% is the healthy range — simpler menus and smaller crews leave more room.
• Full-service: roughly 60–65% is typical and workable, assuming the rest of the cost structure is in line.
• Above 65%: margin is getting squeezed from somewhere — and the breakdown below is how you find out which side.

These are ranges, not laws. A concept with low rent and no debt service can run a slightly higher prime cost and still be healthy; a concept with a heavy lease can’t. Context matters, but if you don’t know your number, you can’t have the conversation about context at all.

Why the labor breakdown matters — FOH, BOH, management, and contract

A single labor percentage tells you that labor is a problem. It doesn’t tell you where. That’s why we always break it into four buckets before drawing any conclusions:

• FOH (front of house): servers, bartenders, hosts. Usually scales with sales volume and service style — watch this ratio drift when you add a service style (counter to full table, for instance) without adjusting staffing.
• BOH (back of house): cooks, prep, dish. Watch this against your menu complexity — a menu that grew faster than the kitchen’s staffing plan is a classic, quiet BOH-cost creeper.
• Management / salaried: this doesn’t flex with a slow week the way hourly labor does, which is exactly why it deserves its own line. A management percentage that’s fine at $70,000 in monthly sales gets uncomfortable fast at $50,000.
• Contract / 1099: consultants, contract chefs, event staff, gig-based delivery drivers. Worth tracking separately for the cost signal — and worth a second look with your accountant, because misclassifying what should be W-2 labor as 1099 contract work is one of the more common (and costly) restaurant compliance mistakes.

Run the four categories side by side against sales, and patterns show up that a single labor number hides completely: a bloated management line at a small location, a BOH that never got staffed back down after a menu simplification, an FOH ratio that’s fine on weekends and bleeding on Tuesdays.

How to calculate your prime cost

Pull your total food and beverage COGS and your total labor cost — broken into FOH, BOH, management, and contract — for the same period as your sales, and run them through our prime cost calculator. It builds the full labor breakdown table automatically, so you can see the total and where it’s coming from in one pass.

What to do when prime cost is too high

The honest answer is “it depends on which side is driving it,” which is precisely why the breakdown matters more than the headline number. A high prime cost driven by food cost points toward menu engineering, portion control, or supplier renegotiation. A high prime cost driven by labor points toward scheduling discipline, or a management structure that’s too heavy for current sales volume. Guessing which one it is — without the breakdown — is how owners end up cutting the wrong thing.

The R.E.Q.M. difference

We’re a Tucson accounting firm that treats prime cost as a weekly number, not a quarterly surprise. Restaurant bookkeeping keeps food cost, labor by category, and prime cost visible every week — not just at month-end. When the number needs a plan instead of just a dashboard, our Restaurant Launch CFO program and ongoing fractional CFO support build the pricing, staffing, and scheduling decisions around it.

Quick answers

What is prime cost in a restaurant? Total food and beverage cost plus total labor cost, expressed as a percentage of sales. It’s the single biggest controllable cost category in the business.

What is a good prime cost percentage? Roughly 55–60% for quick-service concepts and 60–65% for full-service, though the healthy range shifts with your rent and debt structure.

Why break labor into FOH, BOH, management, and contract? Because a single labor percentage hides where the cost is actually coming from. The breakdown shows whether the problem is staffing, scheduling, management overhead, or a menu that outgrew the kitchen’s staffing plan.

How is prime cost different from food cost? Food cost is one input to prime cost. Prime cost adds labor cost to food cost, because the two categories trade off against each other constantly — tracking only one can hide a problem in the other.