I'll admit it: I used to think opening an extra day was a guaranteed money-maker. Turns out, those additional costs (staff, utilities, inventory) often exceed the extra revenue you bring in. Most restaurant owners discover this painful truth only after bleeding money for months.
Why an extra day often results in a loss
Most restaurant owners assume: "One extra day open = more revenue = more profit." That's rarely how the math works out. Your fixed costs keep ticking, even when tables stay empty.
⚠️ Watch out:
An extra day always costs you money (staff, energy, purchasing). You only break even on those costs if you generate enough revenue.
Calculate your break-even point for an extra day
Before you flip that "Open" sign, figure out exactly how much revenue you need to cover your costs. This break-even number tells the whole story.
💡 Example calculation:
Say you're considering Monday service:
- Extra staff: €280 (chef + service)
- Extra energy: €45
- Extra purchasing: €150 (fresh products)
- Other costs: €25
Total extra costs: €500
With a 15% profit margin, you'll need €500 / 0.15 = €3,333 in revenue just to break even.
Estimate realistic revenue
Now comes the reality check. Dig into your current numbers and be brutally honest about what's achievable:
- What's your revenue on your slowest day?
- How many covers do you typically serve on weekdays?
- What's your average check per guest?
💡 Realistic estimate:
A new opening day usually generates 40-60% of your best day:
- Best day: €4,500 revenue
- New day: €1,800 - €2,700 revenue
In this scenario, you'd lose money (break-even was €3,333).
Alternative calculation: contribution margin
Here's another angle: look at your contribution margin - what each dish actually contributes toward covering your fixed costs.
The formula: Contribution margin = Selling price - Variable costs (food + direct labor)
💡 Example contribution:
Pasta carbonara €18.50 (incl. VAT):
- Selling price excl. VAT: €16.97
- Ingredient costs: €5.10
- Variable staff portion: €2.50
Contribution: €16.97 - €7.60 = €9.37 per plate
With €500 in extra fixed costs, you'd need to sell €500 / €9.37 = 53 plates to break even. Something most kitchen managers discover too late is that hitting those plate counts consistently is much harder than it looks on paper.
Test it first with limited opening hours
Don't jump into a full extra day right away. Try these smaller experiments:
- Monday lunch service only (11:00-15:00)
- Sunday happy hour (17:00-19:00)
- Weekend brunch (10:00-14:00)
You'll test customer demand without the crushing weight of full-day fixed costs.
⚠️ Watch out:
Don't forget your own time. If you're working that extra day, factor in €15-25 per hour for your labor.
Monitor carefully in the first months
If you decide to move forward, track these metrics religiously:
- Daily revenue figures
- Cover counts
- Actual costs (labor, utilities, food)
- Average guest check
After 8-12 weeks, you'll have enough data to see if this extra day is sustainable or just bleeding cash. Tools like a food cost calculator can help you track these numbers more accurately.
How do you calculate whether an extra day works out? (step by step)
Calculate all extra costs
Add up: extra staff, energy, fresh purchasing and other costs for that day. These are the fixed costs you'll incur anyway.
Determine your break-even revenue
Divide your extra costs by your net profit margin (usually 10-20%). This is the minimum revenue you need.
Estimate realistic revenue
Look at your quietest day and calculate 40-60% of that. A new day rarely generates more than that in the first months.
Compare break-even with expected revenue
If your expected revenue is higher than your break-even point, it can work out. If not, you'll lose money on that day.
Test first with limited hours
Start with lunch only or happy hour to test demand without full day costs. This minimizes your risk.
✨ Pro tip
Run a 6-week trial period, then evaluate your numbers ruthlessly. If you're not hitting 75% of your break-even target by week 4, cut your losses and close that day.
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
What if I work that extra day myself?
Factor in your own labor costs at €20 per hour for an 8-hour shift. That's €160 in additional costs you need to account for.
How long before a new day becomes profitable?
Typically 3-6 months. Customers need time to adjust to your new hours, and you'll need that time to optimize your operations.
Can't I just gauge demand from reservations?
Reservations help, but many guests walk in without booking. Always calculate using realistic walk-in percentages based on your current patterns.
What if my supplier can't deliver daily?
You'll need larger inventory, which means higher costs and spoilage risk. Build these extra expenses into your break-even calculation.
Should I adjust menu pricing for the extra day?
Some operators test higher prices on slower days to improve margins. Monitor customer response carefully and track average check changes.
Is an extra day always unprofitable initially?
Not always, but frequently. The jump from 5 to 6 days is challenging, and going from 6 to 7 days is typically even tougher.
📚 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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