Restaurants lose an average of 6.5% monthly on excess inventory through spoilage, interest costs, and storage expenses. Your cash gets trapped in ingredients sitting unused while bills keep coming. Here's how to calculate what that excess actually costs you.
Why inventory affects your cash flow
Every euro you spend on inventory is a euro that's not in your bank account. If you buy €5,000 worth of ingredients but only sell €3,000 of it this month, you have €2,000 'stuck' in your cooler.
This gets worse if:
- Your supplier invoices you immediately
- Your guests pay later (with catering or invoice payments)
- Products spoil before you sell them
The real costs of excess inventory
Excess inventory costs you money in 4 ways:
💡 Example calculation:
Restaurant with €50,000 monthly revenue:
- Normal inventory value: €12,500 (25% of revenue)
- Current inventory value: €20,000
- Excess: €7,500
This €7,500 costs you approximately €60 per month in interest costs (1% per month).
1. Interest costs or lost income
Money tied up in inventory can't be invested or used to pay off debts. At 12% annual interest, every €1,000 in extra inventory costs you €10 per month.
2. Spoilage and waste
The longer products sit, the greater the chance they'll spoil. Typical spoilage loss: 3-8% of your inventory value per month.
3. Energy costs
More inventory means fuller coolers and freezers. This increases your energy costs by approximately 15-25%.
4. Storage costs
Extra inventory requires more storage space, which can mean additional rent or expansion.
Step 1: Calculate your current inventory value
Add up everything in your cooler, freezer and dry storage. Calculate using purchase prices, not selling prices.
⚠️ Note:
Only count what you'll actually use. Products that are nearly expired, count at 50% value.
Step 2: Determine your optimal inventory level
A healthy inventory value sits between 20-30% of your monthly revenue. For a restaurant with €40,000 monthly revenue, that's €8,000 - €12,000 in inventory.
Formula for optimal inventory:
Monthly revenue × 25% = Target inventory
💡 Example optimal inventory:
Bistro with €35,000 monthly revenue:
- Optimal inventory: €35,000 × 25% = €8,750
- Current inventory: €15,000
- Excess: €6,250
This excess costs approximately €50 per month in interest costs plus spoilage risk.
Step 3: Calculate the financial impact
Use this formula to calculate the monthly costs of your excess:
Monthly impact = Excess × (Interest% + Spoilage% + Energy%)
Based on real restaurant P&L data, typical percentages are:
- Interest: 1% per month (12% per year)
- Spoilage: 5% per month
- Extra energy: 0.5% per month
- Total: 6.5% per month
💡 Impact calculation:
Excess of €8,000:
- Interest costs: €8,000 × 1% = €80
- Spoilage: €8,000 × 5% = €400
- Extra energy: €8,000 × 0.5% = €40
Total monthly costs: €520
How to optimize your inventory
1. Weekly inventory count
Count your inventory every week. If it consistently rises, you're buying too much.
2. ABC analysis
Divide your ingredients into 3 groups:
- A-products: 80% of your purchases, order daily
- B-products: 15% of your purchases, order 2× per week
- C-products: 5% of your purchases, order 1× per week
3. Just-in-time purchasing
Order just before you need it, not 'just in case'. Better to place one emergency order per week than to consistently have excess inventory.
⚠️ Note:
Too little inventory is also risky. Keep at least 3 days of inventory for your top ingredients, in case a delivery fails.
Digital support for inventory management
Manual inventory checks take a lot of time and are error-prone. A system like KitchenNmbrs helps you with:
- Automatically tracking inventory values
- Alerts when inventory gets too high
- Insight into which products spoil most
- Link between recipes and required inventory
This way you spend less time counting and more time managing the right quantities.
How do you calculate the impact of excess inventory?
Count your current inventory value
Go through your cooler, freezer and dry storage. Add up all products at purchase price. Products that are nearly expired count at 50% value.
Calculate your optimal inventory level
Multiply your monthly revenue by 25%. This is a healthy inventory value. The difference from your current inventory is your excess.
Calculate the monthly costs
Multiply your excess by 6.5% (1% interest + 5% spoilage + 0.5% energy). These are your monthly extra costs from excess inventory.
✨ Pro tip
Track your inventory-to-sales ratio every 2 weeks for 8 weeks straight. If it exceeds 28% more than twice in that period, you're bleeding €200+ monthly in unnecessary holding costs.
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 inventory is normal for a restaurant?
A healthy inventory value sits between 20-30% of your monthly revenue. For a restaurant with €40,000 revenue, that's €8,000-€12,000 in inventory.
What does excess inventory cost me per month?
On average 6.5% of your excess per month. With €5,000 too much inventory, this costs you approximately €325 per month in interest, spoilage and energy costs.
How often should I count my inventory?
At least once per week for a good overview. Count on Monday after the weekend, then you'll immediately see if your planning is on track.
Can I have too little inventory?
Yes, too little inventory means risk of sold-out dishes. Keep at least 3 days of inventory for your main ingredients for emergencies.
Which products should I stock the least?
Fresh products with short shelf life like fish, meat and vegetables. You can order these more frequently in smaller quantities.
How do seasonal fluctuations affect my inventory calculations?
Adjust your target inventory percentage during slow seasons to 20% and busy seasons to 30%. Summer terraces might need 35% due to unpredictable weather affecting sales.
Should I include staff meal ingredients in my excess inventory calculation?
Yes, but calculate them separately at 2-3% of total food cost. Staff meals often use excess inventory, so track this to see if it's actually reducing waste or adding to it.
📚 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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