Prime cost: the mistakes that bleed cash and the method that adds up

What exactly is prime cost, and how do you calculate it properly?

Prime cost is the cost of goods CONSUMED plus total labor cost, divided by net sales excluding tax for the same period, and the healthy range runs from 55% to 62%.

Goods consumed are never purchases: it is opening inventory plus purchases minus closing inventory, with a physical count locked on the last day of the month. Total labor covers wages, tips processed through payroll, social charges, uniforms and staff meals, not merely what shows up on the payroll line. A market-cuisine restaurant in Mexico City was billing 1.18 million pesos a month and its owner swore food cost sat at 29%; the first serious inventory returned 36.4%, because the storeroom had fattened by 214,000 pesos over four months. Purchases are not the cost. The cost is whatever LEFT the storeroom. Every prime cost band describes a different business model rather than a moral grade. Below 52% you usually find bars, counter-service cafés and beverage-heavy operations, where food cost hovers around 22%-26% and payroll barely brushes 26%, with one shift and a minimal crew.

What each prime cost band includes: from 52% to 70%?

The 55% to 62% band is the healthy zone for table service: goods between 28% and 33%, labor between 27% and 31% with charges included.

From 63% to 66% the operation still breathes, though it demands rent under 8% of sales and zero expensive debt for EBITDA to survive. Above 67%, except in high-ticket fine dining, the math stops working: fewer than 33 points remain for rent, energy, card fees —2.35% per transaction according to the Texas Restaurant Association— marketing and profit. That is where closures are born. Five levers explain almost all the prime cost variation between two restaurants of the same size. First, social charges and benefits: adding them in full shifts the indicator by 4 to 7 points in most Latin American operations, and that is precisely the margin the owner believed he had. Second, the sales channel: an order through Uber Eats or DoorDash pays between 15% and 30% commission, with 30% as the standard marketplace rate according to Rezku, so net sales collapse before anything reaches the kitchen.

Five factors that move your prime cost, and how much each one weighs

Third, waste, which costs the U.S. industry roughly $162 billion a year (The Restaurant HQ). Fourth, input inflation, which in Colombia accompanied a 44% drop in sales during 2024 according to Acodrés. And fifth, productivity per labor hour, the only lever that responds within the same week. Dividing by sales with tax included lowers the percentage without lowering a single peso of cost, and it is the quietest error in the trade. With 16% VAT, gross sales of 1,160,000 pesos are 1,000,000 net; if your prime costs add up to 620,000, real prime cost is 62%, yet against the gross figure a reassuring 53.4% appears. Almost nine points of optical illusion. And those nine points get used to set menu prices, to approve one more hire and to sit down with the bank asking for working capital. Here it pays to invert the usual order: decide the denominator first, argue about the result afterward.

The VAT-in-the-denominator error: how 54% is really 62%

As Diego F. Parra, founder of Masterestaurant, puts it, an indicator that changes value depending on who calculates it is not an indicator, it is an opinion formatted as a percentage, and opinions do not pay December's rent. Monthly is the bare minimum and weekly is what separates the owner who corrects from the one who finds out too late. With a monthly close you spot a deviation 45 days after it was born, when you have already spent six weeks buying badly; with a weekly count of the 20 items that concentrate 70%-80% of spend —protein, dairy, oil, liquor— the correction lands in seven days. Picture a concrete scenario: your storeroom grows 50,000 pesos a month for half a year unnoticed, reported prime cost looks two points below reality, you hire two more people against that phantom margin, and in January you stop buying to protect cash.

How often should I close inventory for the number to be useful?

Then consumption shows up in full, all at once, and the bad month was not bad because of operations but because of deferred accounting.

As of August 2026 it remains the trap I see repeated most. Cutting three points of prime cost almost never starts in the kitchen; it starts at the negotiating table and on the schedule. Renegotiate with your three main suppliers on consolidated VOLUME and ask for a fixed price over 90 days on the six items that weigh most in your spend: 4% to 8% improvement is a common opening. Change the channel mix before the recipe, because every point you shift out of marketplace delivery —15% to 30% commission— toward direct orders or the dining room is worth more than any purchasing saving. On cards, U.S. merchants paid $198.25 billion in processing fees during 2025 according to The Motley Fool, so auditing your rate and terminal mix is hard money.

How to negotiate and cut prime cost without touching plate quality?

And in payroll, match your staffing curve to the sales curve by time band. Start tomorrow: physically count your ten most expensive inputs.

When prime cost lands at 58% and the bank account stays dry, the problem is not in the kitchen but below the line. Rent above 10% of net sales, management payroll nobody classified as labor cost, platform commissions booked as marketing, interest on expensive debt and CAPEX paid out of operating cash: that is where the money you keep hunting in food cost actually lives. Profitability in Spanish restaurants fell 0.9% in 2025 on higher costs and regulation, according to Hosteltur, and in the United States full-service chain bankruptcies closed 348 locations in 2024 (Technomic), leaving the segment 18% smaller than in 2019. None of those declines is explained by a two-point food cost. The Masterestaurant discipline is simple and unromantic: measure prime cost properly, then go down through the full P&L, line by line.

Where the money actually leaks?

The gap between purchases and consumption is where money hides. A storeroom that fattens conceals cost that shows up in full the month you stop buying, and that bad month is bad by accounting, not by operation.

Incomplete labor cost hurts more than inflated food cost. Adding taxes and benefits moves prime cost by 4 to 7 points in most Latin American operations, and that is precisely the margin the owner believed he had. Tax in the denominator is the quietest error: it lowers the percentage without lowering the cost. Plenty of owners celebrate a 54% that reads 62% on a net basis, then price against a figure that does not exist. Healthy prime cost with sick cash almost always points at rent and management payroll, not the kitchen. Read the three lines together or do not read them: rent above 8% of sales eats whatever prime cost saved.

Where the money actually leaks — in practice

Plate food cost caps at 32% as a MAXIMUM, never a comfortable target, and payroll, rent and utilities NEVER load onto the plate: they live in break-even, which is a different account and a different decision.