Water seems free, but mineral water can cost you serious money. Many restaurants serve expensive bottled water by default while tap water is often better for your margins. In this article you'll learn exactly how to calculate what water costs per dish and when which choice makes sense.
Why charging for water matters
Water seems like a detail, but at many dishes you serve a glass of water by default. If you have 200 covers per day, that's 73,000 glasses per year. The difference between tap water and mineral water can save hundreds of euros.
💡 Example:
Restaurant with 200 covers/day, 6 days/week:
- Tap water: €0.003 per glass = €234 per year
- Spa blue: €0.18 per glass = €11,232 per year
Difference: €11,000 per year
Calculate tap water costs
Tap water in the Netherlands costs an average of €1.50 per 1000 liters. A standard water glass is 200ml (0.2 liters).
Formula tap water per glass:
€1.50 / 1000 × 0.2 = €0.003 per glass
Add to that:
- Washing costs for glass (soap, energy): approximately €0.02
- Labor time to pour: approximately €0.01
Total tap water costs: €0.033 per glass
Calculate mineral water costs
Mineral water you buy per bottle. Calculate how many glasses you get from one bottle.
💡 Example Spa blue:
- Purchase price: €0.90 per 750ml bottle
- Glasses per bottle: 750ml ÷ 200ml = 3.75 glasses
- Cost per glass: €0.90 ÷ 3.75 = €0.24
Plus washing and labor: €0.24 + €0.03 = €0.27 per glass
Compare different water types
Different brands have different prices per liter. Always calculate back to cost per glass.
💡 Comparison per glass (200ml):
- Tap water: €0.033
- Spa blue (750ml): €0.27
- Evian (500ml, €0.75): €0.33
- San Pellegrino (750ml, €1.20): €0.35
Impact on your food cost
If you serve water by default with each dish, add the water costs to your ingredient costs for the food cost calculation.
⚠️ Note:
If you charge for water separately (€2.50 on the bill), do NOT include it in your food cost. Then it's a separate revenue stream.
For a €25 dish (excl. VAT), tap water means 0.1% additional food cost, while expensive mineral water can add 1.4%.
When to choose which option
The choice depends on your concept and pricing:
- Tap water: For casual dining, bistros, daily menus under €20
- Budget mineral water: For restaurants €20-30, as a service
- Premium water: Fine dining, if you charge for water separately
Many restaurants offer both: tap water free, mineral water for a charge.
Practical purchasing tips
When buying mineral water, pay attention to:
- Price per liter, not per bottle (different bottle sizes)
- Deposit (Spa has no deposit, many others do)
- Expiration date (can be long, but check upon delivery)
- Storage space (tap water requires no inventory)
💡 Purchasing tip:
Buy mineral water per tray or pallet for better purchase prices. A tray of Spa blue (12 bottles) often costs €9-10 instead of €0.90 per bottle individually.
How do you calculate water costs per dish?
Determine your water consumption per guest
Measure how much ml of water you serve by default. Usually this is 200ml for a normal glass. Also note whether you refill and how many glasses per guest on average.
Calculate the cost per glass
For tap water: €1.50 per 1000L ÷ 1000 × 200ml = €0.003. For mineral water: purchase price per bottle ÷ number of glasses from that bottle. Don't forget washing and labor time (approximately €0.03).
Add to your ingredient costs
If you serve water for free, add the costs to your other ingredients for the food cost calculation. If you charge for water separately, calculate the margin on water separately.
✨ Pro tip
Check your water consumption once a week. Count how many bottles you open and divide by number of guests. Often you pour more than you think, especially if staff also drinks from the bottles.
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 tap water always cheaper than mineral water?
Yes, tap water costs approximately €0.033 per glass including washing and labor. The cheapest mineral water costs at least €0.20 per glass. The difference is a factor of 6.
Should I include water costs in my food cost?
Only if you serve it for free. If water is a separate line on the bill (€2.50 for water), then it's a separate revenue stream and you don't include it in food cost.
Which mineral water has the best margin?
Spa blue is often the cheapest to purchase (€0.24 per glass) and has no deposit. For premium concepts you can offer more expensive brands at higher selling prices.
How do I factor in deposit costs?
Deposit is not a cost if you return bottles properly. It is cashflow though: you pay upfront and get it back later. Only breakage or loss becomes a real cost.
Can I use water as a profit center?
Yes, many restaurants charge €2.50-4.00 for a bottle of mineral water that costs €0.90 to purchase. Then you have 65-75% margin on water, which is higher than on food.
📚 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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