BETA APP IN DEVELOPMENT HACCP and more are available in your dashboard — currently in beta, so minor bugs may occur. The updated app with full integration is coming soon.
📝 Purchasing, suppliers & strategy · ⏱️ 2 min read

How do I calculate my margin when a supplier announces a price increase with a three-month notice period?

📝 KitchenNmbrs · updated 14 Mar 2026

Here's an uncomfortable truth: most restaurant owners discover they're losing money weeks after a supplier price hike hits. A 15% increase over three months gives you breathing room, but only if you calculate the real impact on your margins now. You can prevent profit erosion and adjust strategically before it's too late.

What a price increase means for your margin

Supplier price hikes slam your food cost percentage directly. Do nothing? Your margin shrinks. But three months' notice gives you runway to crunch numbers and respond strategically.

💡 Example:

Your steak currently costs €12/kg. In three months it'll jump to €13.80/kg (+15%). Per 250-gram steak:

  • Current cost: €3.00 per portion
  • Future cost: €3.45 per portion
  • Additional expense: €0.45 per steak

Serving 50 steaks weekly = €1,170 extra annual costs

Calculate your new food cost percentage

Ingredient price jumps reshape your food cost percentage. You need to know exactly where you'll land.

Formula: New food cost % = (New ingredient costs / Selling price excl. VAT) × 100

💡 Example:

Steak dish: €32.00 incl. 9% VAT

  • Selling price excl. VAT: €29.36
  • Current ingredient costs: €9.50 (food cost 32.4%)
  • Future ingredient costs: €10.95 (food cost 37.3%)

Food cost jumps from 32.4% to 37.3% - unsustainable territory!

Three strategic responses

This one represents one of the most common blind spots in kitchen management - having advance notice but failing to act decisively. You've got options:

  • Response 1: Increase selling price to maintain current food cost
  • Response 2: Source alternative suppliers with better pricing
  • Response 3: Modify the dish (different protein cut, adjusted portion size)

⚠️ Reality check:

Inaction is a decision too, but you're choosing reduced profitability per dish. High-volume items can drain thousands annually.

Calculate your new minimum selling price

Want to preserve your food cost percentage? You'll need to determine the required selling price adjustment.

Formula: New selling price excl. VAT = New ingredient costs / (Target food cost % / 100)

💡 Example:

Maintaining 32% food cost:

  • New ingredient costs: €10.95
  • Target food cost: 32%
  • Required price excl. VAT: €10.95 / 0.32 = €34.22
  • Required price incl. VAT: €34.22 × 1.09 = €37.30

Price adjustment needed: €32.00 to €37.30 - a €5.30 increase

Impact on your total revenue

Calculate the full financial impact and gauge customer price sensitivity:

  • Tally monthly portion sales for affected dishes
  • Multiply by additional cost per portion
  • This reveals your monthly profit impact

Food cost management tools automatically compute price increase impacts across your entire menu, highlighting dishes requiring immediate attention.

How do you calculate the impact of a price increase?

1

Calculate the new ingredient costs

Take your current ingredient costs per dish and increase them by the supplier's percentage. At 15% price increase: current costs × 1.15.

2

Calculate your new food cost percentage

Divide the new ingredient costs by your selling price excl. VAT and multiply by 100. This shows you how high your food cost will be.

3

Determine your new selling price

Divide your new ingredient costs by your desired food cost percentage. Multiply by 1.09 for the price incl. VAT on your menu.

✨ Pro tip

Set calendar reminders every 6 weeks to review supplier pricing across your top 20 ingredients. Price creep often happens gradually, and catching 3-5% increases early prevents the shock of discovering 15-20% margin erosion months later.

Calculate this yourself?

In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.

Try KitchenNmbrs free →

Was this article helpful?

Share this article

WhatsApp LinkedIn

Frequently asked questions

Should I raise prices immediately after a supplier price increase?

Not automatically, but calculate the impact first. Food costs exceeding 35% typically signal profit erosion requiring swift adjustment.

Is switching suppliers always the better option?

Quality and reliability matter more than marginal savings. Inconsistent deliveries or inferior ingredients can damage your reputation and cost more long-term.

How should I communicate menu price increases to customers?

Be transparent about rising costs while emphasizing quality and value. Stagger increases across different dishes rather than implementing wholesale changes simultaneously.

What happens when multiple suppliers increase prices simultaneously?

This typically occurs during inflationary periods or seasonal supply constraints. Calculate per-dish impacts and prioritize adjustments for your highest-volume items first.

Do I calculate food costs including or excluding VAT?

Always calculate food cost percentages using prices excluding VAT. Your menu displays VAT-inclusive prices, but food cost calculations require the net amount.

How far in advance should I lock in supplier contracts to avoid price volatility?

Six to twelve month contracts provide stability for core ingredients. However, ensure contracts include quality guarantees and reasonable price adjustment clauses for extreme market conditions.

ℹ️ This article was prepared based on official sources and professional expertise. While we strive for current and accurate information, the content may differ from the most recent regulations. Always consult the official authorities for binding standards.

📚 Sources consulted

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.

JS

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.

🏆 8 years kitchen manager at 1NUL8 Group Rotterdam
Expertise: food cost management HACCP kitchen management restaurant operations food safety compliance

Optimize your purchasing with data

Know exactly which supplier is most cost-effective and how price changes affect your margins. KitchenNmbrs links purchasing directly to recipe costs. Try it free for 14 days.

Start free trial →
Disclaimer & terms of use

Table of Contents

💬 in 𝕏