Calculating fish margins is like comparing apples to oranges - the sticker price tells only half the story. Many restaurant owners forget to factor in extra costs like transport, time and waste. Your actual margin depends on understanding the complete cost picture from different sourcing channels.
All costs of fish auction vs wholesaler
The price per kilo of fish is just one part of your total cost price. For a fair comparison, you need to include all costs:
- Purchase price per kilo: what you pay the supplier
- Transport costs: fuel, time, vehicle wear and tear
- Labor time: what does your time or your chef's time cost?
- Waste and quality differences: how much do you throw away?
- Trimming loss: whole fish vs. ready-made fillets
💡 Example:
Sole from the auction vs. wholesaler:
- Auction: €18/kg + €15 transport + 2 hours labor (€50) = €83 for 4kg
- Wholesaler: €22/kg delivered = €88 for 4kg
True cost price auction: €20.75/kg vs wholesaler €22/kg
Calculate trimming loss and yield
Whole fish from the auction has more trimming loss than ready-made fillets from the wholesaler. This affects your true price per kilo:
- Whole fish: 45-55% trimming loss (head, bones, skin, fins)
- Fillets from wholesaler: 5-10% trimming loss (trimming only)
The formula for true cost price after trimming loss:
True price = Purchase price / (Yield % / 100)
💡 Example:
Whole sea bass from auction vs. fillets from wholesaler:
- Auction: €20.75/kg, 50% trimming loss → €20.75 / 0.50 = €41.50/kg fillet
- Wholesaler: €22/kg fillets, 8% trimming loss → €22 / 0.92 = €23.91/kg
Wholesaler is €17.59/kg cheaper!
⚠️ Watch out:
Many business owners only calculate the purchase price and forget trimming loss. Then the auction seems cheaper while you're actually paying more per portion.
Include time and labor costs
A trip to the fish auction costs time - and that time has real value. Travel time round trip usually runs 1-3 hours, plus another 30-60 minutes for waiting and shopping. But that's not all.
- Travel time round trip: usually 1-3 hours
- Waiting and shopping time: 30-60 minutes
- Extra processing time: cleaning whole fish takes more time
Calculate with an hourly rate of €25-30 for yourself or your chef. At 3 hours you're spending €75-90 on labor time alone.
Compare quality and shelf life
Fresh fish from the auction can have quality advantages, but also carries risks. A pattern we see repeatedly in restaurant financials shows quality issues can destroy margins faster than high purchase prices.
- Auction advantages: day-fresh, often superior flavor, local story for marketing
- Auction risks: variable quality, no guarantee of availability
- Wholesaler advantages: consistent quality, reliable delivery schedules
💡 Example:
If you get bad fish 1 out of 10 times at the auction:
- 10% waste = 10% higher true cost price
- €41.50/kg becomes €45.65/kg
Still more expensive than wholesaler at €23.91/kg
Situations where auctions win
The fish auction can be more economical in specific situations:
- Large volumes: from 20-30kg you spread transport costs effectively
- Short distance: auction within 30 minutes drive
- Combined trips: you drive past it anyway for other shopping
- Specialty items: fish the wholesaler doesn't stock
For smaller restaurants using less than 15kg fish per week, the wholesaler usually wins on total cost. Tools like KitchenNmbrs can help track these real costs over time.
How do you calculate true cost price? (step by step)
Calculate all purchasing costs
Add all extra costs to the purchase price: transport (fuel + wear and tear), labor time (number of hours × €25-30), parking costs. Divide this by the total number of kilos to get the true purchase price per kilo.
Correct for trimming loss
Measure how much usable product you have left after processing. Calculate the yield percentage and divide the true purchase price by this percentage. Formula: true price = purchase price / (yield % / 100).
Compare the final prices
Put the true cost price per kilo of usable product side by side. Don't forget to factor in quality differences and waste (bad deliveries). Choose the channel that offers the best price-to-quality ratio.
✨ Pro tip
Track your true cost per usable kilogram from both channels for 6 weeks straight. Most operators underestimate processing time by 40% and miss significant cost differences that add up to hundreds of euros annually.
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
Is fish from the auction always fresher than from the wholesaler?
Not necessarily. Quality wholesalers receive daily shipments and maintain proper cold storage. Always check the eyes, gills and smell to assess freshness, regardless of your source.
How often should I adjust my fish prices?
Fish prices fluctuate weekly due to seasonal changes, weather conditions and catch volumes. Check your cost price every two weeks and adjust menu pricing if food costs exceed 35%.
Can I deduct transport costs from my taxes?
Yes, business transport costs are tax-deductible. Track mileage, fuel costs and trip purposes carefully. Consult your accountant about current mileage allowances.
How do I calculate labor costs for processing time?
Use €25-30 per hour for trained kitchen staff. Filleting whole fish takes 2-3 minutes per piece, so processing 20 fish equals one hour of labor costs.
⚠️ EU Regulation 1169/2011 — Allergen Information — https://eur-lex.europa.eu/eli/reg/2011/1169/oj
The allergen information on this page is based on EU Regulation 1169/2011. Recipes and ingredients may vary by supplier. Always verify current allergen information with your supplier and communicate this correctly to your guests. KitchenNmbrs is not liable for allergic reactions.
In the UK, the FSA enforces allergen regulations under the Food Information Regulations 2014.
📚 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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