What percentage of guests will have dietary requirements?

In the UK, about 14% of adults follow some meat-free diet (vegetarian, vegan or pescatarian), of whom roughly 6-7% are strictly vegetarian and about 3% vegan (Finder/Vegan Society, end 2025). Around 10% of consumers buy gluten-free and about 6% of adults have a confirmed food allergy, of which tree-nut allergy affects roughly 2% (Coeliac UK; FSA/Allergy UK). The default 14% vegetarian figure deliberately counts everyone who needs a vegetarian-suitable meal, since vegans and pescatarians are happy with the same option. These groups overlap, so a single vegan gluten-free dish covers several requirements at once.

Should I ask guests about dietary requirements?

Always. The calculator provides estimates using UK averages, but you should collect actual requirements from your guest list via RSVP cards or a group message. Some requirements like severe allergies are safety-critical and must be confirmed directly.

How many extra meals should I prepare?

Add a 10% buffer across all categories. For special dietary meals, round up generously - it is better to have one spare vegan meal than to leave someone without food. Leftover special meals can usually be enjoyed by anyone.

What about overlapping dietary requirements?

Many requirements overlap. A vegan gluten-free meal satisfies vegetarian, vegan, dairy-free and gluten-free requirements simultaneously. Plan your most restrictive options first (vegan + GF) and work outwards. This reduces the total number of different meal types needed.

Dietary Requirements Calculator — Free Food & Catering Tool

How We Calculate This

The calculator estimates meal counts from guest numbers and UK dietary percentages, with a configurable buffer for extras.

Default UK percentages

Vegetarian: 14% (everyone wanting a meat-free option)
Vegan: 4%
Gluten-free: 8%
Dairy-free: 5%
Halal: 5%
Kosher: 1%
Nut allergy: 2%
Other allergy: 3% (in Advanced options)

These are adjustable to match your specific guest demographics. The defaults are deliberately rounded up as a catering safety margin and are drawn from ONS Census 2021 (Muslim 6.0%, Jewish 0.4% — not all keep halal/kosher, so the 1% kosher default is a generous estimate), Finder and the Vegan Society (meat-free ~14%, vegan ~3%), Coeliac UK (~10% buy gluten-free, ~1% coeliac) and FSA/Allergy UK (food allergy ~6%, tree-nut ~1.8%).

Headline vs breakdown

The per-category breakdown rows list each requirement separately, so a guest who is both vegan and gluten-free is counted in both rows. Their sum therefore exceeds the "Special diet meals" headline, which applies an overlap factor of ~30% (about 30% of people with a requirement have more than one) to estimate the number of unique guests needing a special meal. Use the headline for the unique guest count and the breakdown to brief the caterer on each dish type.

Frequently Asked Questions

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Last updated: March 2026

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