Waste after a catering event can seriously eat into your profit margin. Many caterers estimate the damage, but don't know exactly how much money literally goes into the trash. In this article you'll learn step by step how to calculate waste costs exactly, so you can plan better for your next events.
What are waste costs in catering?
Waste costs are all ingredients you've purchased and prepared, but haven't sold. In catering this happens often because you have to estimate in advance how many people will come and what they'll eat.
- Purchased too much for the number of guests
- Wrong estimate of popular dishes
- Leftover buffet items
- Spoiled ingredients due to poor planning
The three types of waste
To calculate exactly what you're losing, split your waste into three categories:
💡 Example breakdown:
- Purchasing waste: Too many ingredients ordered
- Preparation waste: Mise-en-place that's left over
- Service waste: Full buffet at end of event
Calculate your purchase value
First add up what you purchased for this event. Calculate per ingredient:
- Number of kilos × price per kilo
- Add up all ingredients
- Don't forget: spices, oil, butter, garnish
⚠️ Note:
Only count ingredients specifically purchased for this event. Don't use stock you already had.
Measure what you throw away
After the event, weigh everything that goes in the trash. Divide this into:
- Unprepped: Ingredients you didn't use
- Prepped but not served: Finished food that's left over
- Preparation waste: Peels, trim scraps, etc.
💡 Example calculation:
Event for 100 people, €25 per person:
- Total purchase: €1,200
- Thrown away unprepped: 8 kg (€95 value)
- Thrown away prepared food: 12 kg (€180 value)
- Normal preparation waste: 5 kg (€30 value)
Total waste: €305 (25.4% of purchase)
Calculate the real costs
Waste costs are more than just ingredient price. Also factor in:
- Labor costs: Time spent preparing wasted food
- Energy costs: Gas/electricity for preparation
- Disposal costs: Extra waste costs extra money
Rule of thumb: multiply your ingredient costs by 1.4 for total waste costs.
💡 Total impact calculation:
From the example above:
- Ingredients wasted: €305
- Labor + energy + disposal: €305 × 0.4 = €122
- Total waste costs: €427
This is €4.27 per person less profit.
Turn it into an improvement plan
Use these numbers to plan better for your next events:
- Which dishes were left over the most?
- How much waste percentage is acceptable? (standard: 5-10%)
- Can you still sell or store leftover food?
Digital tracking helps
Many caterers track waste costs in an app like KitchenNmbrs. This shows you per event:
- Exact cost price per person
- Waste percentage relative to purchase
- Trends across multiple events
- Which dishes are most profitable
⚠️ Note:
Measure the first 3-5 events very precisely. After that you can get by with rough estimates, because you'll recognize patterns.
How do you calculate waste costs? (step by step)
Register all purchases for the event
Make a list of all ingredients you specifically purchased for this event. Note per ingredient: number of kilos, price per kilo, and total price. Add everything up for your total purchase value.
Weigh all waste after the event
Divide what you throw away into three categories: unprepped ingredients, prepared food that's left over, and normal preparation waste. Weigh each category separately and note the weight.
Calculate the value of wasted ingredients
Figure out how many euros worth of ingredients you threw away. For prepared dishes, estimate the ingredient value. Multiply by 1.4 to factor in labor and energy costs.
✨ Pro tip
Photograph your buffet at the beginning and end of each event. This way you can visually see which dishes are popular and which are left over, without having to weigh everything.
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 waste is normal in catering?
Standard waste is between 5-10% of your total purchase. Above 15% you'll noticeably lose profit. With buffets it's often higher than with plated service.
Should I count normal preparation waste?
Peels and trim scraps don't count as waste - that's normal preparation waste. Only count what you could have sold but now throw away.
Can I still use leftover catering?
Cold dishes you can sometimes sell the next day. Hot dishes not due to food safety. Be conservative: if you're unsure, count it as waste.
How do I prevent too much waste at buffets?
Plan for 10% fewer guests than attending and refill as needed. Put popular dishes up front and expensive items in back. Monitor during the event what runs out quickly.
Should I count labor costs in waste?
Yes, because your chef spent time preparing food that gets thrown away. Rule of thumb: multiply ingredient costs by 1.4 for total waste costs.
📚 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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