Allergen labelling
How to emphasise allergens on a food label
UK guidance permits four ways to make an allergen stand out: bold type, capital letters, contrasting colours or underlining. Any one satisfies the requirement — but only one of them survives a monochrome thermal printer.
Reviewed against official guidance.SourcesNot legal advice.
The four permitted methods
What the guidance says
Allergenic ingredients can be emphasised “by bold type, capital letters, contrasting colours or through underlining”.
| Method | Example | Survives |
|---|---|---|
| Bold | wheat flour | Most printing; can be weak in a light typeface |
| Capitals | WHEAT flour | Everything, including monochrome thermal |
| Contrasting colour | wheat flour | Colour printing only — lost on thermal, photocopies and for readers who cannot distinguish it |
| Underlining | wheat flour | Larger type; closes up and smudges at small sizes |
Which to choose
Bold capitals. It is the only combination that works on every printer a small food business is likely to own, and it does not depend on the reader’s colour vision or on the label staying clean.
If your whole ingredients list is already in capitals — common on thermal labels — capitals alone stops distinguishing anything. Use bold as well, or set the rest of the list in sentence case.
Chocolate Brownie
Ingredients: Caster sugar, Butter (MILK), Free range EGGS, Dark chocolate (cocoa mass, sugar, cocoa butter, emulsifier: SOYA lecithin), WHEAT flour, Cocoa powder, Sea salt.
Two shapes of allergen
Almost every ingredient falls into one of two cases.
The allergen is written in the name
“Wheat flour”, “soya lecithin”, “milk chocolate”, “egg yolk”. Emphasise the allergen word where it stands and leave the rest alone:
WHEAT flour · emulsifier: SOYA lecithin · MILK chocolate
The allergen is not written in the name
“Butter”, “mayonnaise”, “pesto”, “cheese”. The ingredient still has to be named, so the allergen is added in brackets after it:
Butter (MILK) · Mayonnaise (EGG, MUSTARD)
Don’t replace the ingredient with the allergen
Writing “MILK” where the ingredient is butter deletes information the customer is entitled to — they can no longer see that the product contains butter. Add the allergen; do not substitute it.
Every occurrence, not just the first
The guidance is explicit: allergenic ingredients “must be emphasised every time they appear in the ingredients list”. Milk in the butter and milk again in the caramel means two emphasised mentions.
Salted Caramel Brownie
Ingredients: Caster sugar, Butter (MILK), Free range EGGS, Dark chocolate (cocoa mass, sugar, cocoa butter, emulsifier: SOYA lecithin), WHEAT flour, Salted caramel (sugar, cream (MILK), butter (MILK), sea salt), Cocoa powder.
This is the rule most often missed, and it is missed innocently — somebody bolds the first one, sees the allergen is declared, and moves on.
The name-of-food exception
Emphasis is not required “where the name of the food clearly refers to the allergen concerned, such as ‘milk’”. For a bottle of milk, nobody needs the word bolded.
For a made product with a full ingredients list it rarely helps, and it turns a mechanical task into a judgement call. Emphasising anyway costs nothing.
Four ways it goes wrong
- A “Contains” line instead of emphasis. The allergens have to be emphasised inside the list. A summary underneath is an extra, not a substitute.
- Emphasis inside brackets forgotten. The soya inside the chocolate needs it as much as the wheat outside.
- Colour only. Fine on a colour proof, invisible on the thermal printer you actually use.
- Emphasising the whole ingredient. “BUTTER” tells a reader nothing about which allergen it is. “Butter (MILK)” does.
Questions
Is bold on its own enough?
Can I use a coloured box or a symbol instead?
Official sources
Everything on this page traces back to these. Where they and we disagree, they are right — tell us and we'll fix it.
- Labelling guidance for prepacked for direct sale (PPDS) food productsFood Standards Agency / GOV.UK
- Food allergen labelling and information requirements technical guidanceFood Standards Agency / GOV.UK
- Food labelling: giving food information to consumersGOV.UK
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