The 14 Major Allergens Under UK Law: 2026 Compliance Guide

UK law names 14 allergens that every food business must be able to identify and declare. Getting this right is not optional and it is not just paperwork — it is the difference between a safe meal and a potentially fatal reaction. This guide covers all 14 allergens, the foods that obviously contain them and the hidden sources that catch businesses out, and exactly how you must declare them across prepacked, PPDS, loose and distance-selling food in 2026.

The 14 major allergens and the law behind them

The legal foundation for allergen labelling in Great Britain is the Food Information Regulations 2014 (FIR 2014), which retained the requirements of EU Regulation 1169/2011 after the UK left the EU. Annex II of that regulation sets out 14 substances or products that are the most common causes of food allergies and intolerances in the population. Any food business that prepares, handles or sells food must be able to declare whether any of these 14 allergens are present in the food it offers.

The 14 allergens are: celery, cereals containing gluten, crustaceans, eggs, fish, lupin, milk, molluscs, mustard, peanuts, sesame, soybeans, sulphur dioxide and sulphites, and tree nuts. The list is fixed in law — you cannot add to it or remove from it, and you cannot group several allergens together under a vague heading such as "nuts" or "seafood". Each one must be named specifically wherever it is present.

It is worth emphasising from the outset that allergen accuracy is the food business operator's legal responsibility. Software such as FoodCore — including its recipe-driven allergen matrix and auto-bolded PPDS labels — is a tool to help you record, calculate and communicate allergen information consistently, but it is not a compliance authority. You must verify your allergen declarations against your suppliers' specifications and against current FSA allergen guidance. With that framing in place, here is the full reference table.

Reference table: the 14 allergens, common and hidden sources

Allergen	Common sources	Hidden / less-obvious sources
Celery	Celery sticks, celeriac, salads, soups, stocks	Stock cubes, gravy, celery salt, spice mixes, ready meals, sauces, "vegetable" flavourings
Cereals containing gluten	Wheat, rye, barley, oats, spelt; bread, pasta, cakes, pastry, batter	Soy sauce, beer, malt vinegar, stock cubes, dusting flour, some sausages, sauces thickened with flour, communion wafers
Crustaceans	Crab, lobster, prawns, langoustines, shrimp, scampi	Shrimp paste in Thai/SE Asian dishes, fish stocks, surimi, prawn crackers, some Worcestershire-style sauces
Eggs	Whole eggs, omelettes, quiche, mayonnaise, cakes, meringue	Egg glaze on pastry, fresh pasta, some breads, mousses, marshmallow, lecithin (E322 may be egg-derived), some wines (fining)
Fish	Cod, salmon, tuna, fish fingers, fishcakes, fish pie	Worcestershire sauce (anchovies), Caesar dressing, fish sauce, some pizza toppings, gelatine/isinglass (fining agent in some drinks)
Lupin	Lupin flour, lupin seeds, some Continental and gluten-free breads	Gluten-free baked goods, pastries, pancakes, pasta — lupin flour is increasingly used as a wheat substitute
Milk	Milk, butter, cheese, cream, yoghurt, milk powder	Casein/caseinate, whey, lactose, "natural flavouring", ghee, some crisps, processed meats, dark chocolate, bread glazes
Molluscs	Mussels, oysters, clams, scallops, squid, snails, whelks	Oyster sauce, fish stocks, paella mixes, some fish soups and seafood sauces
Mustard	Mustard, mustard powder, mustard seeds, English/Dijon mustard	Salad dressings, marinades, mayonnaise, sauces, soups, processed meats, curry powder, piccalilli, some breads
Peanuts	Peanuts, peanut butter, satay, some snacks	Groundnut/arachis oil, some curries and sauces, baked goods, "may contain" snack mixes, some vegetarian products
Sesame	Sesame seeds, tahini, hummus, sesame oil, seeded buns	Burger buns and bread, halva, falafel, some salad dressings, dukkah, breadcrumb coatings
Soybeans	Soy sauce, tofu, edamame, soya milk, miso, tempeh	Soya lecithin (E322) in chocolate and baked goods, vegetable oils, processed meats, some breads, "vegetable protein"
Sulphur dioxide / sulphites	Wine, dried fruit, some soft drinks (declared above 10 mg/kg or 10 mg/litre)	Dried apricots, some sausages and burgers, pickled foods, vinegars, fruit juices, prepared potato products, E220–E228
Tree nuts	Almonds, hazelnuts, walnuts, cashews, pecans, brazils, pistachios, macadamia	Marzipan, praline, nut oils, pesto, some sauces and desserts, "natural flavouring", nut butters, some cereals and bars

Cereals containing gluten

This allergen is broader than many people assume. The regulations cover wheat, rye, barley, oats, and the wheat relatives spelt and kamut (khorasan wheat), along with their hybridised strains. On a label you must name the specific cereal — for example "wheat flour" rather than simply "flour" — and emphasise it. Note that "gluten-free" is a separate, additional claim governed by maximum gluten thresholds; a product can be free from one named cereal yet still contain another.

The obvious sources are bread, pasta, cakes, biscuits, pastry and batter. The hidden sources are where businesses slip up: malt vinegar and beer derive from barley, many soy sauces contain wheat, stock cubes and gravy granules often contain wheat flour, and dusting flour on a worktop or a proving basket can transfer gluten to an otherwise gluten-free product. Sausages, processed meats and some sauces are routinely thickened with wheat flour. Oats deserve a specific note: they are naturally gluten-free but are very commonly contaminated with wheat during growing and milling, so they are named separately in the regulations and must be declared.

Peanuts versus tree nuts

UK law treats these as two entirely separate allergens, and conflating them is one of the most common and most dangerous labelling errors. Peanuts (also called groundnuts or monkey nuts) are a legume that grows underground — botanically closer to peas and beans than to nuts. Tree nuts are a distinct list named explicitly in the regulations: almonds, hazelnuts, walnuts, cashews, pecans, brazil nuts, pistachios, macadamia and Queensland nuts.

You must never merge these into a single "nuts" declaration. A customer allergic only to peanuts may safely eat almonds, and vice versa, so a blanket "contains nuts" both fails the legal requirement to name the specific allergen and removes useful information from the people who need it most. Watch for hidden sources: groundnut (arachis) oil is peanut-derived; marzipan and praline contain almonds; pesto usually contains pine nuts and sometimes cashews; and "natural flavouring" can mask nut derivatives. For the avoidance of doubt, coconut and pine nuts are not classified as tree nuts under UK allergen labelling, although individuals may still react to them.

The seafoods: fish, crustaceans and molluscs

The regulations split aquatic allergens into three separate entries, and again you cannot collapse them into "seafood". Fish covers all finned fish such as cod, salmon, tuna and anchovy. Crustaceans are the shelled, jointed-leg group: crab, lobster, prawns, shrimp, langoustines and scampi. Molluscs are a fourth, separate group including mussels, oysters, clams, scallops, squid, snails and whelks.

The hidden sources here are notorious. Worcestershire sauce contains anchovies (fish); Caesar dressing typically contains anchovies; Thai and South-East Asian dishes frequently use fish sauce and shrimp paste; oyster sauce contains molluscs; and surimi (imitation crab sticks) contains crustacean. Fish stocks and seafood sauces can carry more than one of these allergens at once. Isinglass, a fining agent derived from fish, is found in some traditional beers and wines — relevant if you sell drinks or use them in cooking. Because these three allergens appear so often as background ingredients in sauces and condiments, they are a frequent cause of mislabelling in kitchens that do not realise a bought-in sauce contains them.

Eggs and milk

Eggs appear obviously in omelettes, quiche, mayonnaise, meringue and most cakes, but they are also used as a glaze on pastries and bread, in fresh pasta, in mousses and marshmallow, and as lecithin (E322) which may be egg-derived. Eggs are also used to fine some wines. Milk is one of the most pervasive hidden allergens because of the many forms dairy takes: casein and caseinate, whey, lactose, butterfat and milk powder all derive from milk and must be declared. Ghee is clarified butter and still counts. Less obvious milk-containing products include many crisps and savoury snacks, some processed meats, certain dark chocolates, and bread glazes. "Natural flavouring" can sometimes contain milk derivatives, which is why your supplier specifications matter so much.

The seeds and legumes: sesame, mustard, celery, soybeans and lupin

These five allergens are united by how easily they hide inside compound ingredients. Sesame is obvious in tahini, hummus and seeded buns, but it is also routinely baked into burger buns and bread, used in halva, falafel and dukkah, and present in some breadcrumb coatings and dressings. Mustard appears far beyond the jar of mustard: in salad dressings, mayonnaise, marinades, soups, processed meats, curry powders and piccalilli. Celery — including celeriac and celery seed — is a backbone of stocks, soups, gravies and spice mixes, and celery salt is an easily overlooked source.

Soybeans are present not only in soy sauce, tofu, edamame and miso but in soya lecithin (E322), which is extremely common in chocolate and baked goods, and in some vegetable oils and processed meats. Lupin is the allergen most businesses forget exists. Lupin flour and lupin seeds are increasingly used as a wheat substitute, so lupin turns up in gluten-free baked goods, pastries, pancakes and pasta. There is a recognised cross-reactivity between lupin and peanut, so customers with a peanut allergy may also react to lupin — another reason to declare it accurately rather than assume it is rare.

Sulphur dioxide and sulphites

This is the only allergen on the list with a concentration threshold. Sulphur dioxide and sulphites (the additives E220 to E228) must be declared when present at a concentration of more than 10 mg/kg or 10 mg/litre, expressed as total SO₂. They are used as preservatives and to maintain colour. Common sources are wine, dried fruit and some soft drinks; hidden sources include dried apricots, some sausages and burgers, pickled foods, vinegars, fruit and vegetable juices, and prepared potato products. Because the obligation depends on concentration, this is one allergen where your supplier's specification is essential — you cannot judge it by sight or taste.

Practical tip: the single biggest cause of allergen errors is the bought-in compound ingredient — the sauce, stock cube, seasoning blend or glaze whose own ingredient list contains an allergen you did not expect. Build your allergen records from supplier specification sheets, not from memory or from the front of the pack. In FoodCore, each ingredient carries its own allergen profile derived from the supplier declaration, and any allergen present in a sub-recipe automatically propagates up into every finished product that uses it.

How to declare the 14 allergens

Identifying allergens is only half the job. UK law also dictates how you communicate them, and the rules differ depending on how the food is sold. There are four main situations.

Prepacked for direct sale (PPDS) — Natasha's Law

PPDS food is food that is packaged on the same premises from which it is sold, before the customer orders it — think a sandwich wrapped that morning and put on a shelf, or a cake boxed ready for sale. Since October 2021, Natasha's Law has required every PPDS item to carry the product name and a full ingredients list, with all of the 14 allergens present emphasised within that list — most commonly in bold. The emphasis applies to the allergen word itself (for example wheat flour, milk, egg), not to a separate "contains" line. For a fuller breakdown of the obligations, see what Natasha's Law requires and our 2026 compliance refresher.

FoodCore generates PPDS labels directly from your recipe data, with the 14 allergens auto-bolded inside the ingredients list and the ingredients ordered by weight. Because the label is a live reflection of the recipe rather than a separate document, changing a recipe updates the label automatically — which is exactly the kind of dedicated Natasha's Law labelling software the situation calls for.

Loose and non-prepacked food

Loose or non-prepacked food includes meals served in a cafe or restaurant, food sold from a deli or bakery counter, and items packed at the customer's request. Here you do not need a full ingredients list. Instead you must make allergen information available for each item and signpost clearly where customers can find it. The information can be provided in writing — on a menu, a ticket, a label or a notice — or it can be given verbally, but if it is verbal you must display clear signposting (for example, "Ask a member of staff about allergens"). Crucially, verbal information must be accurate and consistent every time, so staff need a reliable written reference to read from behind the counter. A sign telling customers to ask is not sufficient if staff then cannot answer accurately.

Distance selling and online orders

For distance selling — your website, an app, phone orders, mail order, or third-party delivery platforms — allergen information must be provided twice. First, it must be available before the purchase is completed, at the point the customer chooses the food, and without any extra charge. In practice this means listing the allergens against each item on the website, app or menu. Second, the same allergen information must be provided again at the point of delivery, when the physical food reaches the customer — for example printed on the packaging, on a sticker, or on an accompanying menu or leaflet. Providing it in only one of these two places does not meet the requirement.

Prepacked for retail

Food that is fully prepacked for general retail sale — wrapped and labelled before being offered for sale, including to another business or for sale somewhere other than where it was made — carries the most detailed obligations. It must show a full mandatory ingredients list with the 14 allergens emphasised, plus the other mandatory particulars such as the legal product name, net quantity, durability date, storage conditions, business name and address, and (in most cases) a nutrition declaration. The allergen emphasis rules are the same as for PPDS: the allergen is highlighted within the ingredients list itself.

Warning — "Contains" statements and "may contain": Where a food has an ingredients list, you must emphasise the allergens within that list. A separate "Contains: milk, egg" statement cannot replace that emphasis on labelled food, and you must never list an allergen that is genuinely an ingredient only in a "may contain" warning. Precautionary "may contain" labelling is voluntary and is only for the risk of unintentional cross-contamination — it should follow a real risk assessment and be specific, never a blanket disclaimer slapped on everything. Deliberate ingredients always go in the ingredients list or allergen information.

Keeping declarations accurate over time

Allergen compliance is not a one-off setup; it is an ongoing discipline. The most common way a once-correct label becomes wrong is a change you did not re-check: a supplier reformulates a product and adds an allergen, you swap an ingredient for a cheaper alternative, or a recipe is tweaked without the label being regenerated. Each of these can silently invalidate an existing declaration. Good practice is to review allergen information whenever a recipe or supplier changes, to keep supplier specification sheets on file, and to maintain a dated record of when allergen data and labels were last updated — the kind of evidence an Environmental Health Officer will want to see.

This is precisely the work that an allergen matrix tool is built to automate. FoodCore maintains a recipe-driven allergen matrix across your whole range and recalculates every affected product when an ingredient's allergen profile changes, so a single supplier update flows through to every label and matrix entry that depends on it. FoodCore plans start at £19/month (Essentials) and £55/month (Core), and there is a 7-day free trial with no card required — you can sign up at signup.foodcore.io. To be clear, though, the legal responsibility for accurate allergen declarations remains with you as the food business operator: use the software to stay organised and consistent, and verify against current FSA guidance.

Selling in the US too? If you ship or sell into the United States as well as the UK, the allergen rules are different — the US recognises nine major allergens under FALCPA and uses "Contains" statements rather than in-list emphasis. FoodCore now has a US/FDA compliance mode controlled by a single Compliance Region setting (UK, US, or Both), so the same recipe data can produce correctly formatted labels for either market. See our FDA vs UK food labelling comparison and the US compliance software page for more. This guide, though, is UK-first — get your 14 allergens right at home before you worry about exporting.

Further resources

The 14 major allergens: frequently asked questions

What are the 14 major allergens in the UK?

UK law requires 14 allergens to be declared: celery, cereals containing gluten (wheat, rye, barley, oats, spelt and kamut), crustaceans (such as crab, lobster and prawns), eggs, fish, lupin, milk, molluscs (such as mussels, oysters and squid), mustard, peanuts, sesame, soybeans, sulphur dioxide and sulphites (at concentrations above 10 mg/kg or 10 mg/litre), and tree nuts (almonds, hazelnuts, walnuts, cashews, pecans, brazils, pistachios, macadamia and Queensland nuts). These are the allergens set out in Annex II of the Food Information Regulations 2014. The list is the same whether you sell prepacked food, prepacked for direct sale (PPDS) food, or loose food.

Do I have to list allergens in bold?

On any food that carries an ingredients list — including prepacked food and PPDS food labelled under Natasha's Law — each of the 14 allergens must be emphasised so it stands out from the rest of the ingredients. Bold is the most common method, but you can also use a contrasting colour, underlining, capitals or a different font, provided it is genuinely distinguishable. You emphasise the allergen word itself within the list (for example wheat flour, milk, egg), not a separate statement. For loose food that carries no ingredients list, bolding does not apply; instead you must make the allergen information available another way, such as on a menu, a chalkboard or verbally with clear signposting.

What is the difference between peanuts and tree nuts under UK law?

UK law treats peanuts and tree nuts as two separate allergens. Peanuts (also called groundnuts or monkey nuts) are a legume that grows underground, not a true nut. Tree nuts are a distinct group that the regulations name specifically: almonds, hazelnuts, walnuts, cashews, pecans, brazil nuts, pistachios, macadamia and Queensland nuts. A product can contain one without the other, so you must declare them separately and never merge them into a single 'nuts' entry. Coconut is not classified as a tree nut for allergen labelling purposes under UK law, although some people are allergic to it. Pine nuts are also not on the list, though they can cause reactions.

How do I declare allergens for loose or unpackaged food?

For loose or non-prepacked food — meals served in a cafe, food sold from a deli counter, cakes sold individually without packaging — you do not need a full ingredients list. You must make allergen information available for each item and tell customers where to find it. The information can be written (on a menu, label, ticket or notice) or given verbally, but if it is verbal you must clearly signpost that customers can ask staff, for example with a sign saying allergen information is available on request. Verbal information must be accurate and consistent, so staff need a reliable written reference behind the counter to read from. Pointing customers to a sign that says only 'ask a member of staff' is not enough on its own if staff cannot then give accurate answers.

Are 'may contain' warnings legally required?

No. 'May contain' and similar precautionary allergen labelling (PAL) statements are voluntary in the UK, not a legal requirement. They are used to warn about the unintentional presence of an allergen through cross-contamination — for example where the same equipment handles nuts and nut-free products. A 'may contain' statement must never be used as a substitute for declaring an allergen that is a deliberate ingredient: deliberate ingredients must always appear in the ingredients list or allergen information. Precautionary statements should only be applied after a genuine risk assessment of cross-contamination, and should be specific rather than a blanket 'may contain everything' applied to all products, which undermines their usefulness to allergic customers.

What about allergens in distance selling and online orders?

For distance selling — online orders, phone orders, mail order and food ordered through third-party platforms — allergen information must be provided twice. First, it must be available before the purchase is completed, at the point the customer chooses the food, and it must not carry an extra charge. This usually means listing allergens on the website, app or menu at the point of choice. Second, the allergen information must be provided again at the moment of delivery, when the physical food reaches the customer, for example on the packaging, on a sticker, or on an accompanying menu or leaflet. Providing it only once — either online or only on delivery — does not meet the requirement.