Food cost usually runs high because of several small leaks, not one disaster: counts that happen too rarely, supplier price creep, portion drift, untracked waste, recipe costs frozen at opening prices, over-ordering, and the gap between theoretical and actual cost. Each one adds a point or two. Weekly counts and a waste log show which ones are yours.
Your food cost crept up again this month, and you can't point to why. Nothing obvious changed — same menu, same suppliers, same crew. The money is leaking somewhere you can't see.
Food cost almost never blows up in one dramatic event. It drifts, a point or two at a time, through leaks that are invisible one by one. Here's how to find yours.
What's a "normal" food cost, anyway?
Normal depends on your concept, so the most useful benchmark is your own number, measured the same way every week. A common rule of thumb puts many full-service kitchens somewhere around 30% of food sales, with protein-heavy concepts like steakhouses running higher. Treat any published range as a starting point, not a standard. The formula is simple:
(Beginning inventory + purchases − ending inventory) ÷ food sales
The formula gives you the kitchen-wide number. For a single dish, food cost is ingredient cost ÷ menu price, and if you'd rather not do that math on a napkin, our free food cost calculator does it per dish, no signup required.
Two things about that formula trip people up. First, it requires inventory counts — without a real beginning and ending number, you're computing purchases ÷ sales, which hides everything that spoiled, walked away, or got over-portioned. Second, most operators calculate it monthly, which means a problem can burn cash for five weeks before the P&L admits it. Weekly is the cadence that catches problems while they're still small.
Your actual food cost (the formula above) also differs from your theoretical food cost, which is what you'd spend if every plate were made exactly to recipe. The gap between them is where waste, theft, and portioning errors hide. We cover that in the variance report guide.
Culprit 1: You're not counting inventory (or not often enough)
Without counts, you literally cannot know your food cost — you can only know what you bought. Walking the coolers every day catches outages; it doesn't catch a freezer that's carrying $1,800 more than it should, or usage that's quietly outrunning sales.
Weekly counts expose problems in days instead of months. If counting takes your team three hours on a clipboard, that's a process problem — a small team can count a 200-product kitchen in well under an hour when the count is organized by storage area and split across people.
Culprit 2: Supplier price creep
Suppliers rarely announce increases. The case of chicken that was $62 in January is $67 in June, and nobody noticed because nobody compares invoice lines week over week.
Wholesale food prices move every month. USDA's Economic Research Service tracks wholesale and farm-level food prices and updates its forecast monthly in the Food Price Outlook. Your invoices are where those moves land, one line at a time.
The compounding math is brutal: a 3% average increase across 50 products on $15,000 of weekly purchasing is roughly $23,000 a year — for the same food. Check your five most expensive ingredients against an invoice from three months ago. If you find creep on those, it's everywhere.
Culprit 3: Portion drift
The recipe says 6 oz. The line cook who's been slammed all week is pouring 8. That's a 33% cost increase on that ingredient, invisible until you weigh plates.
Portion drift is a standards problem, not a people problem. Fixes that work: recipe cards with exact weights at every station, portion tools (scoops, ladles, scales) sized to the spec, and periodic spot-checks where you weigh a dish during service. If you've never done this, start with your three highest-volume proteins — that's where drift costs the most.
Culprit 4: Waste you're not tracking
Every kitchen throws food away. The problem isn't the waste — it's untracked waste. If the wilted case of greens and the dropped tray and the over-prepped batch all go in the trash unlogged, your food cost absorbs them silently and you never learn which one is a pattern.
Logging waste with a reason — expired, spoiled, dropped, over-prepped — turns the trash can into data. After a month you'll know whether your problem is ordering too much, prepping too much, or a walk-in that needs a thermostat.
Culprit 5: Recipe costs frozen in time
You costed your menu when you opened. Ingredient prices have moved every month since. The pasta dish you priced at a 30% food cost two years ago may be running 38% today — and because it sells well, it's dragging your whole average up with volume.
Recipe costs need to update when ingredient prices update, automatically, from what you actually paid on recent invoices — not from a spreadsheet you revisit annually. This is exactly the kind of bookkeeping software should do for you: Rinvy recalculates recipe and menu-item costs from a weighted average of what you paid on your receipts, so the number you see is current, not historical.
Culprit 6: Over-ordering and slow inventory turns
"Order extra just in case" is an expensive habit. Excess inventory ties up cash, crowds storage, and — for anything perishable — becomes Culprit 4 on a delay.
The fix is ordering from data instead of gut: par levels for stable items, burn rate (how fast you actually use a product) for everything else. If your order list comes from what you counted and what you're projected to run out of, over-ordering mostly disappears on its own.
The EPA makes the same point from the waste side. Its Wasted Food Scale puts prevention, buying and preparing only what is needed, at the top, and inventorying supplies is one of the simple prevention steps it names for businesses.
Culprit 7: The variance gap
Add up culprits 3 through 6 and you get the gap between theoretical and actual food cost. A small gap is normal, because trim and the odd dropped plate never fully go away. A gap that widens from one count to the next, or sits on the same expensive products every week, is money walking out the door through portioning, unlogged waste, staff meals nobody records, or theft.
You can't manage the gap until you can see it, ranked by dollar impact per product. A 50% variance on parsley is a rounding error; a 3% variance on ribeye is real money. Here's how variance analysis works and how to set it up.
Your action plan for this week
- Count inventory. This week, full kitchen. It's the prerequisite for everything else.
- Start logging waste — with reasons, every shift. Even two weeks of data tells a story.
- Re-cost your top 10 menu items against current ingredient prices. Re-price or re-portion what's drifted.
- Pull invoices from 90 days ago and compare your 5 most expensive ingredients. Confront creep with your rep — prices are more negotiable than they look.
None of this requires new software — a clipboard and a spreadsheet can do all four, slowly. The reason operators use Rinvy is speed and persistence: counts in minutes instead of hours, waste logged from your phone, recipe costs that update themselves, and invoices that log themselves from a photo. The free plan covers counts, waste logging, price change alerts, and menu-item food cost for a 50-product kitchen, enough to find your first leak.