Most U.S. restaurant operators use "food cost" and "cost of goods sold" (COGS) interchangeably — and that confusion costs them money on both sides of the P&L. Food cost is a percentage. COGS is a dollar amount. They are related but not the same, and using the wrong one in the wrong place leads to bad pricing decisions and ugly tax surprises.
What is food cost?
Food cost (or food cost percentage) is a ratio. It tells you what share of your net revenue is consumed by ingredients:
Food cost % = (Ingredient cost / Net revenue) × 100
This is the number you use for menu engineering, pricing decisions, and benchmarking against NRA industry data (typically 25-35% for healthy operations).
📊 Example:
A burger sold at $14.00 with $4.20 in ingredients:
Food cost: 30%
What is COGS (cost of goods sold)?
Cost of goods sold is a dollar amount. It is the total inventory consumed in a period — calculated correctly using the inventory equation that the IRS expects on your tax return:
COGS = Beginning inventory + Purchases - Ending inventory
Note: COGS is not the same as "what you bought this month." It is what you actually used, which means inventory swings affect the number.
📊 Example:
- Beginning inventory (Mar 1): $8,500
- Purchases during March: $14,000
- Ending inventory (Mar 31): $9,200
COGS for March: $8,500 + $14,000 - $9,200 = $13,300
Why does the distinction matter?
Three places where confusing them hurts you:
- Tax filing: the IRS requires COGS on Schedule C / 1120 / 1120-S using the inventory equation. Reporting "purchases" instead of true COGS misstates taxable income and can trigger audits.
- Pricing decisions: menu engineering needs food cost percentage, not COGS dollars. A $4.20 ingredient cost on a $14 burger means nothing without the percentage context.
- Period comparisons: COGS shifts with inventory levels even if you bought the same amount. Food cost percentage normalizes for that, which is why it is more useful for trend tracking.
The relationship between food cost and COGS
They link together cleanly:
Food cost % = (COGS / Net revenue) × 100
So COGS is the dollar input, food cost percentage is the ratio output. Both are needed for different purposes:
- COGS: for your accountant, your tax return, your P&L
- Food cost %: for your operations team, menu engineering, supplier negotiations
⚠️ Critical:
Inventory the same way every period. Take physical counts on the same day of the month, value at the same method (FIFO, LIFO, weighted average), and stick to it. Inconsistent inventory makes COGS look like it is swinging when it is just your counting method drifting.
How U.S. tax law treats this
Under IRS rules, restaurants typically use the cash method or accrual method of accounting:
- Cash method: available to most small restaurants under $25M annual gross receipts. Track COGS via the inventory equation but recognize purchases when paid.
- Accrual method: required above $25M and recommended for accuracy. COGS reflects actual usage in the period regardless of when invoices were paid.
Either way, COGS goes on your Schedule C (sole prop), 1120-S (S-corp), or 1120 (C-corp) — calculated using the inventory equation, not "what we bought."
Practical takeaway
Use the right number in the right context:
- Pricing a new menu item? Food cost percentage.
- Comparing this month to last? Food cost percentage.
- Filing taxes or running the P&L? COGS.
- Reviewing supplier contracts? Both. COGS shows total exposure, food cost percentage shows whether you can afford it.
How to calculate COGS for your tax return (step by step)
Take a physical inventory at period start
Count and value all food and beverage on hand at the start of the period (month, quarter, year). Use a consistent valuation method (most U.S. restaurants use weighted average or FIFO).
Track all purchases during the period
Sum all food and beverage invoices for the period. This is your gross purchases — not yet COGS.
Take a physical inventory at period end
Count and value all food and beverage on hand at the end of the period using the SAME method as step 1. Inconsistency between start and end counts will distort COGS.
Apply the inventory equation
COGS = Beginning inventory + Purchases - Ending inventory. This is what the IRS expects on your tax return. NOT "total purchases" — that misstates your taxable income.
✨ Pro tip
Take physical inventory on the same day of the month every time, at the same time of day, ideally before the morning prep shift starts. Consistency in measurement is more important than perfection — drift in your counting method makes COGS look like it is moving when it is not.
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Frequently asked questions
Are food cost and COGS the same thing?
Does the IRS require the inventory equation for restaurants?
Can I use cash basis accounting and still calculate COGS?
How often should I take physical inventory?
Sources consulted
- EU Verordening 852/2004 — Levensmiddelenhygiëne (2004) — Official source
- EU Verordening 853/2004 — Hygiënevoorschriften voor levensmiddelen van dierlijke oorsprong (2004) — Official source
- EU Verordening 1169/2011 — Voedselinformatie aan consumenten (2011) — Official source
- NVWA — Hygiënecode voor de horeca (2024) — Official source
- NVWA — Allergenen in voedsel (2024) — Official source
- Codex Alimentarius — International Food Standards (2024) — Official source
- FSA — Safer food, better business (HACCP) (2024) — Official source
- BVL — Lebensmittelhygiene (HACCP) (2024) — Official source
Food Standards Agency (FSA) — https://www.food.gov.uk
The HACCP standards shown in this application are for informational purposes only. KitchenNmbrs does not guarantee that displayed values are current or complete. Always consult the FSA or your local authority for the latest regulations.
Written by
Jeffrey Smit
Founder & CEO of KitchenNmbrs
Jeffrey Smit built KitchenNmbrs from 8 years of hands-on experience as kitchen manager at 1NUL8 Group in Rotterdam. His mission: give every restaurant owner control over food cost.
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