A 5% unnoticed food cost increase can wipe out €15,000 in annual profit for an average restaurant. Your dish costs shift weekly as suppliers adjust prices, seasons change, and recipes evolve. Most restaurant owners calculate food costs once, then never touch them again.
A 5% unnoticed food cost increase can wipe out €15,000 in annual profit for an average restaurant. Your dish costs shift weekly as suppliers adjust prices, seasons change, and recipes evolve. Most restaurant owners calculate food costs once, then never touch them again.
Why food costs constantly change
Your food cost isn't a fixed number. Every week things happen that affect your food cost:
- Suppliers raise prices (sometimes without notice)
- Seasonal products become more or less expensive
- Your chef adjusts recipes or gives larger portions
- New ingredients become available
- Product quality changes (more trimming loss)
💡 Example:
Your steak costs €24/kg in January. Due to inflation and bird flu, the price rises to €28/kg in March. Your food cost rises from 28% to 33% without you noticing.
Impact: €1.20 less profit per steak
How often to recalculate? (per category)
Not all dishes need the same update frequency:
Check weekly
- Fish and seafood: Prices fluctuate weekly
- Seasonal vegetables and fruit
- Your top 3 revenue-generating dishes
Check monthly
- Meat (beef, pork, lamb)
- Dairy products
- Dishes with expensive ingredients (truffle, lobster)
Check quarterly
- Pasta, rice, dry goods
- Herbs and spices
- Oils and vinegars
- Dishes you sell infrequently
⚠️ Note:
Always check after switching suppliers or making large purchases. New suppliers often have different portion sizes or quality.
Signs that you need to recalculate
Don't wait for your schedule. Watch for these signals:
- Invoices: Do you see price increases on your purchase invoices?
- Portion size: Is your chef giving different portions than planned?
- Complaints: Are guests complaining about smaller portions? Then your food cost doesn't match
- Margin feeling: Do you feel like you're earning less?
- Seasons: Summer/winter changes in vegetables and fruit
💡 Example impact:
Restaurant with 100 covers/day, 6 days/week:
- Food cost rises €0.50 per dish
- You don't adjust menu price
- Loss: €0.50 × 100 × 6 × 52 = €15,600/year
Practical approach: the 80/20 rule
Focus your time on the dishes that have the most impact:
- 80% of your profit comes from 20% of your dishes
- Check your top 5 revenue drivers first
- Then update the expensive ingredients in other dishes
- Cheap side dishes can be checked monthly
I've seen restaurants ignore this principle — a mistake that costs the average restaurant €200-400 per month in missed profit opportunities. The pasta special that sells 15 portions daily deserves more attention than the weekend lamb special that moves twice monthly.
Digital vs. manual tracking
Recalculating food costs takes time. Compare your options:
Excel/manual
- Advantage: Free, full control
- Disadvantage: Time-consuming, error-prone, no automatic updates
Digital system
- Advantage: Quick updates, fewer errors, overview
- Disadvantage: Monthly costs
💡 Time savings:
Manual: 2 hours per month for 20 dishes
Digital: 20 minutes per month
Savings: 1 hour 40 minutes per month
How do you update food costs systematically?
Create an update schedule
Note for each dish when you last calculated its food cost. Plan weekly checks for fish and seasonal products, monthly for meat, and quarterly for dry goods.
Check supplier invoices
Compare your latest invoice with last month's. Watch for price increases and note which ingredients have become more expensive. Even small increases add up over a whole year.
Recalculate and adjust
Update the new purchase prices in your food cost calculation. Check if your food cost is still within your desired margin (usually 28-35%). If not, consider adjusting your menu price.
✨ Pro tip
Recalculate costs every time you switch to a new batch/lot of your main protein. Different suppliers often have varying trim loss percentages — your 80% yield assumption might actually be 72%, quietly eating your margins.
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In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
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Frequently asked questions
Should I recalculate costs immediately when my supplier sends a price increase notice?
Yes, but prioritize by volume and margin impact first. Update your three highest-selling dishes within 24 hours, then work through the rest by weekly sales volume. Don't waste time on low-volume items until you've protected your main profit drivers.
How do I handle ingredients that fluctuate daily, like fresh fish market prices?
Build a 15-20% buffer into your fish dish pricing to absorb daily fluctuations. Check actual costs twice weekly and adjust portions slightly rather than changing menu prices constantly. Most guests won't notice a 10g portion adjustment, but they'll definitely notice daily price changes.
What's the biggest red flag that my food costs are outdated?
Your theoretical food cost (recipe-based) is significantly lower than your actual food cost (inventory-based). If there's more than a 3-4% gap consistently, your recipe costs are probably stale and you're operating blind.
📚 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
- Warenwetbesluit Bereiding en behandeling van levensmiddelen (2024) — Official source
- WHO — Foodborne diseases estimates (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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