Allergen information is the one piece of nutrition data that chain restaurants generally do publish, because getting it wrong has consequences that calorie counts do not. It is still not as simple as reading a label, and the gap between what a menu declares and what a kitchen does is where the real risk sits.
What the law actually requires
Two things, in most of the markets we track. First, that allergens present as ingredients are declared. Second, that the information is available to a customer before they order - Whether printed on the menu, in a folder at the counter, or provided verbally on request.
The list of declarable allergens differs by jurisdiction, which matters if you are travelling.
| Region | Declarable allergens | Notable inclusions |
|---|---|---|
| EU and UK | 14 | Celery, mustard, lupin, sulphites, molluscs |
| United States | 9 major allergens | Sesame added in 2023 |
| Australia and New Zealand | Broadly similar to EU, plus lupin | Sesame declared |
| Several Asian markets | Varies widely | Requirements are less uniform |
Celery and mustard are the two that catch people out most often when travelling from the United States to Europe, because they are declarable there and not at home. A menu that is silent about them in one market is not necessarily free of them.
Ingredients versus kitchens
This is the distinction that matters most and the one menus communicate least well. A declared allergen list describes the recipe. It does not describe the fryer, the grill, the prep surface, the tongs or the person assembling the order during a rush.
The ingredient list is a document. The kitchen is a process. Only one of them is published.
In a quick-service kitchen, shared equipment is not an occasional lapse - It is the design. Fryers are shared by default. Grills cook multiple proteins. Assembly happens at speed on a shared surface. That is why "may contain" statements exist, and why they should be read as genuine risk information rather than legal throat-clearing.
If you have a serious allergy
Published menu data - Including everything on this site - Describes ingredients. It cannot tell you about cross-contact in a specific kitchen on a specific day. For a diagnosed allergy, speak to the staff, ask specifically about shared fryers and shared surfaces, and treat the answer from the restaurant as authoritative over anything you read online.
What our data shows
Across 15,775 items, 2,165 carry allergen information from the source menu - About 14%. That is by far the best-covered nutrition field we hold, against 955 items with dietary tags and 29 with calorie counts.
Coverage is uneven by market and by brand, and it broadly tracks regulatory pressure. Brands operating in the UK, Ireland and the EU publish allergen data most consistently, because the requirement to have it available before ordering is enforced and well established.
Where an item on this site carries allergen data, we reproduce exactly what the source menu declared, without interpretation. Where it does not, we show nothing - We never infer an allergen from an item name, because "cheeseburger" tells you about one allergen and nothing about the other thirteen.
How to ask well at the counter
The quality of the answer depends a great deal on the question. Four that work:
- "Do you have the allergen information?" Most outlets have a folder or a screen. This is a routine request and staff are trained for it.
- "Is the fryer shared?" The single most useful question in a fast-food kitchen, and the one least likely to be answered by a printed menu.
- "Can this be prepared separately?" Sometimes yes, usually with a wait. Asking at a quiet time gets a better answer than asking at peak.
- "Which items do you recommend for this allergy?" Staff at chains with strong allergen training often know the safest items on their own board better than any document.
Travelling with an allergy
Three things change at a border: the declarable allergen list, the recipe for the same product name, and the language of the conversation. All three matter.
A product sold under an identical name in two markets can have different ingredients, because supply chains are local. Our comparison tool will show you where two markets' menus diverge, which is a useful signal that recipes may differ - but it is a signal, not a substitute for asking.
For a broader view of what different markets publish, see calorie labelling rules by country, and for meat-free ordering specifically, vegetarian and vegan fast food.
