What percentage of guests are typically vegetarian?

In the UK, around 5-10% of the population is vegetarian and 2-3% is vegan, but this varies hugely by age group and location. For younger crowds (18-30), expect 15-20% vegetarian/vegan. Always ask guests directly rather than guessing, but these percentages are useful for initial planning.

Do I need separate menus for each dietary requirement?

Not necessarily. A well-planned menu can cover multiple requirements. For example, a vegan and gluten-free main course covers vegans, vegetarians, dairy-free and gluten-free guests in one dish. Aim for 3-5 menu options that between them cover all requirements.

What is the overlap factor?

The overlap factor accounts for guests who have multiple dietary requirements — for example, someone who is both vegan and gluten-free. A factor of 1.3 means the raw total of requirements is divided by 1.3 to estimate the actual number of people. The 1.3 default is a PartyCalcs planning estimate (roughly a 30% overlap), not a measured statistic; adjust it in Advanced Options if you know your guests, or set it to 1.0 to treat every requirement as a separate person.

How many spare portions should I order?

Order 10% extra portions as a minimum. This covers last-minute guests, guests who change their mind, and dietary requirements not declared in advance. For allergen-specific dishes (nut-free, gluten-free), order at least 2 spare portions regardless of numbers.

Dietary Requirements Tracker

Track dietary needs for your event and calculate exact counts for each requirement.

Total Guests

Total number of people attending

% Vegetarian

UK average ~5%; allow 15-20% for an under-30 crowd. Ask guests where you can.

% Vegan

UK average ~2% (YouGov 2026); higher for younger guests.

% Gluten-Free

Coeliac is ~1%, but ~3.7% of UK adults eat gluten-free by choice.

% Nut Allergy

Peanut/tree-nut allergy affects ~0.5% of UK adults; plan higher if children attend.

% Dairy-Free

Lactose intolerance plus allergy and choice; ~5% is a safe planning figure.

% Halal

Set to match guests requiring halal-certified food.

% Kosher

Set to match guests requiring kosher-prepared food.

How We Calculate This

This calculator converts dietary requirement percentages into exact guest counts and estimates menu planning needs.

How it works

Count per requirement = total guests × percentage (rounded up)
Total with restrictions = sum of all counts ÷ overlap factor (capped at total guests)
Overlap factor (default 1.3) accounts for guests with multiple requirements — it is a PartyCalcs planning estimate, not a measured statistic, and you can adjust it in Advanced Options
Menu options = 1 standard + 1 each for vegetarian, vegan and gluten-free + 1 combined halal/kosher option. Dairy-free and nut-allergy guests are catered for within those dishes rather than adding their own option

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Adjust quantities based on your guests and event type.