Running discount promotions is like pouring water into your wine – it might look like more, but you've diluted what matters most. Many restaurant owners forget that discounts automatically increase food cost percentages while shrinking margins. Your ingredient costs don't change, but your selling price drops, creating a profit squeeze that catches owners off guard.
Why discounts increase your food cost
Your food cost percentage gets calculated based on actual selling price. Give a discount and your selling price drops, but ingredient costs stay exactly the same. This automatically pushes your food cost percentage higher.
💡 Example:
Normal situation:
- Menu price: €32.00 (incl. VAT)
- Selling price excl. VAT: €29.36
- Ingredient costs: €9.00
- Food cost: 30.7%
With 20% discount:
- Selling price with discount: €23.49 excl. VAT
- Ingredient costs: €9.00 (stays the same!)
- Food cost: 38.3%
Your food cost jumps from 31% to 38%
The impact on your margin per dish
Beyond higher food costs, you've got fewer euros left per dish to cover fixed expenses. This hits profitability directly and hard.
💡 Example of margin impact:
Normal dish (€32.00):
- Ingredients: €9.00
- Margin for staff/rent/profit: €20.36
With 20% discount (€25.60):
- Ingredients: €9.00
- Margin for staff/rent/profit: €14.49
You lose €5.87 margin per dish
⚠️ Important:
A 20% discount doesn't mean you make 20% less profit. The impact's much bigger because your fixed costs stay the same.
How to explain this to your team
Your team needs to understand discounts aren't 'free money'. Use concrete numbers to show what they actually cost.
- Show the real food cost: "This dish normally runs 31% food cost, with discount it becomes 38%"
- Calculate it back to volume: "We need to sell 30% more just to break even"
- Make it personal: "Every discount we give means less budget for wage increases"
From tracking this across dozens of restaurants, the most effective approach is showing staff the actual euro amount lost per discounted dish. Numbers don't lie, and they make the impact crystal clear.
When discounts make sense
Discounts can work strategically, but you need to know the impact and find compensation elsewhere.
- Slow-moving items: Better to discount than waste completely
- Volume compensation: If you're certain you'll sell significantly more
- Customer retention: For regulars who might otherwise leave
- Competition: If you'd otherwise lose market share
💡 Break-even calculation:
With 20% discount you need 30% more volume for the same profit:
- Normal margin per dish: €20.36
- Margin with 20% discount: €14.49
- Extra volume needed: €20.36 ÷ €14.49 = 1.40 (40% more)
Not selling 40% more? Then you're losing money.
Alternative actions with less impact
There are smarter ways to attract guests without hammering your margins so hard:
- Free side dish: Costs only ingredients (€2-3) instead of €6 discount
- Offer upgrades: "For €3 extra you get the premium version"
- Bundle deals: Starter + main course for fixed price
- Loyalty card: After 10 visits get 1 free (spreads costs over time)
How to track and monitor this
To stay on top of promotion impacts, you need to track what discounts actually cost you.
- Record every discount with reason and amount
- Calculate your average selling price per dish weekly
- Compare actual food cost with target food cost
- Track whether volume increases compensate for discounts
A food cost calculator like KitchenNmbrs shows you per dish what discounts do to your food cost and whether promotions actually turn profitable.
How do you calculate the impact of discounts? (step by step)
Calculate your normal food cost percentage
Divide your ingredient costs by your selling price excluding VAT and multiply by 100. This is your baseline to measure the impact of discounts.
Calculate the new selling price with discount
Subtract the discount percentage from your menu price and calculate back to excluding VAT. This becomes your new basis for the food cost calculation.
Calculate the new food cost and margin impact
Divide the same ingredient costs by the lower selling price for your new food cost. Also calculate how much margin you lose per dish and how much extra volume you need.
✨ Pro tip
Track your discount impact for 2 weeks before committing to any promotion longer than that. Calculate exactly how many extra covers you need daily to break even – most promotions fail this test within 10 days.
Calculate this yourself?
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
How much extra volume do I need to compensate for a 20% discount?
You need approximately 40% more volume to break even with a 20% discount. The formula is: normal margin divided by discounted margin. Most restaurant owners underestimate this significantly.
Can I give discounts without increasing my food cost percentage?
No, every price discount automatically increases your food cost percentage because ingredient costs stay the same while selling price drops. You can only limit the impact by choosing smarter alternatives like free sides or upgrades.
What's the biggest mistake restaurants make with discount promotions?
They focus only on increased sales volume without calculating the break-even point. A 20% discount that brings 15% more customers actually loses money, but many owners don't realize this until they review monthly numbers.
📚 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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