How to Cost a Bulk Buffet Menu to Hit Your Target GP (UK)
To cost a bulk buffet menu and hit a target gross profit (GP), work out the total ingredient cost per head, then divide that cost by your target food cost percentage to set the price. If you want a 70% GP, your food cost must be 30% of the selling price — so a buffet costing £4.50 per head needs to sell at £15 (£4.50 ÷ 0.30). Buffets add extra layers of risk because of over-catering and plate waste, so you build a wastage buffer into the cost before you price. That's the whole method. The rest of this article shows you how to do it accurately.
Step 1: Decide your target GP first
In the UK, most kitchens aim for 65–70% gross profit on food, which is the same as a 30–35% food cost. Buffets sit at the tighter end because portion control is harder, so many operators target 68–72% GP and price defensively.
The formula you'll use throughout:
- Food cost % = (ingredient cost ÷ selling price) × 100
- Selling price (ex VAT) = ingredient cost ÷ target food cost %
- GP % = 100 − food cost %
Everything below feeds into these three lines.
Step 2: Cost every dish per portion, not per recipe
You can't cost a buffet by eye. Break each dish down to the cost per portion using this approach:
- List every ingredient in the recipe.
- Record the pack price and pack size you actually buy (e.g. 5 kg bag of rice at £6.50).
- Calculate the unit cost (£6.50 ÷ 5,000 g = £0.0013 per g).
- Multiply by the quantity used in the recipe.
- Divide the total recipe cost by the number of portions it yields.
Worked example for a chicken curry serving 20:
| Ingredient | Pack price | Used | Cost |
|---|---|---|---|
| Chicken thigh | £5.20/kg | 3 kg | £15.60 |
| Onions | £0.80/kg | 1.5 kg | £1.20 |
| Curry base/spices | — | — | £3.40 |
| Coconut milk | £1.10/400ml | 1.6 L | £4.40 |
| Rice | £1.30/kg | 2 kg | £2.60 |
| Total | £27.20 |
£27.20 ÷ 20 portions = £1.36 per portion.
Do this for every dish going on the buffet.
Step 3: Account for yield and waste
Raw ingredient weight is not the same as usable weight. This is where buffet costings quietly leak profit.
- Trim and prep loss: A whole chicken, vegetables to peel, or fish to fillet lose weight. Apply a yield percentage. If a vegetable yields 80% usable, your effective cost is
unit cost ÷ 0.80— so it's 25% higher than the raw price suggests. - Cooking loss: Meat can lose 20–30% of its weight during cooking. If you portion cooked, cost on the cooked yield.
Skipping yield adjustments is the single most common reason UK kitchens miss their target GP. A dish that looks like 30% food cost on paper can be 38% in reality.
Step 4: Build a per-head cost by predicting consumption
A buffet doesn't sell fixed portions — guests help themselves. You need a consumption forecast per head, not a plate spec.
A workable UK starting point for a mixed hot buffet:
- Protein: 150–200 g per head
- Carbohydrate (rice/potato/pasta): 150 g per head
- Vegetables/sides: 120 g per head
- Bread/starters: 60–80 g per head
- Dessert: 100–120 g per head
Multiply your per-portion dish costs by these consumption figures to get a realistic cost per head. Guests take more of cheap carbs and less of expensive protein — but they also come back for seconds, so don't under-forecast.
Say your forecast lands at £4.50 per head in ingredients.
Step 5: Add a wastage and over-production buffer
Buffets must always look full, which means you cook more than you'll serve. Add a buffer to your per-head cost:
- Over-production buffer: 10–20% depending on service length and refill policy.
- Plate/return waste: food left on plates and unrepurposable pans.
At £4.50 per head with a 15% buffer, your true working cost is £4.50 × 1.15 = £5.18 per head. Price off this number, not the clean recipe number.
Step 6: Price to hit your target GP
Now apply the formula. Using £5.18 per head and a 70% GP target (30% food cost):
- Selling price ex VAT = £5.18 ÷ 0.30 = £17.27 per head
Then handle VAT. Restaurant food in the UK is standard-rated at 20%, so the menu (VAT-inclusive) price is:
- £17.27 × 1.20 = £20.72 per head
Round to a sensible £21 per head. Always calculate GP on the ex-VAT figure — GP is never measured on the VAT-inclusive price, or you'll overstate your margin.
Step 7: Sanity-check and stress-test
Before you commit:
- Recalculate GP at the real numbers. If your actual per-head cost creeps to £5.60, GP at £17.27 drops to 68%. Know your break point.
- Test the low-attendance scenario. Buffets have fixed prep costs. If you cater for 100 and 70 turn up, your effective per-head cost rises because production doesn't scale down neatly. Set a minimum number in the booking terms.
- Separate labour and overheads. GP only covers food cost. Your net profit still has to absorb staff, energy, and rent, which is why hitting a healthy GP matters so much on high-volume buffets.
Step 8: Lock in specs and re-cost regularly
Ingredient prices move constantly in the UK. A costing done in January can be wrong by March. Protect your GP by:
- Writing standard recipes with fixed quantities so anyone can reproduce the dish at cost.
- Re-costing monthly or when a supplier price changes by more than 5%.
- Tracking actual vs theoretical usage after each service to expose over-portioning and waste.
Quick reference
- GP % = 100 − food cost %
- Price ex VAT = per-head cost ÷ target food cost %
- Menu price = price ex VAT × 1.20
- Always adjust for yield, cooking loss, and a waste buffer before pricing.
- Aim for 68–72% GP on buffets and set a minimum guest number.
If you'd rather not build all this in a spreadsheet by hand, try the free food cost calculator at getprepsheet.com/calculator to check any dish's cost and GP in seconds — and if you want ready-made costing templates that handle yields, portions and batch scaling for you, take a look at the Excel templates in the shop at getprepsheet.com/shop.
Run the free calculator → · See the templates → · Save your recipes free →