How to Label Fragrance Allergens on Cosmetics (UK & EU)

Fragrance makes a cosmetic appealing but it is also the most common cause of allergic reactions, which is why certain fragrance allergens must be declared individually on the label. The rules here are detailed, recently expanded, and frequently misunderstood, especially by makers using essential oils. This guide explains which allergens to declare, at what levels, and how to show them correctly.

Allergen declaration sits within the ingredient list; see our guide to INCI ingredient lists for the wider context, and consider an allergen review to identify what is in your fragrance.

Why fragrance allergens are declared separately

Most of a fragrance can be covered on the label by the single word “Parfum”. But a defined set of fragrance components are known to cause allergic contact reactions in susceptible people, and for these the law requires individual declaration so that allergic consumers can identify and avoid them. Someone allergic to, say, linalool or limonene needs to see those names on the pack, not have them hidden inside a generic “Parfum”.

This is a consumer protection measure, and it applies regardless of whether the fragrance is synthetic or natural. That last point is crucial: essential oils are rich natural sources of these very allergens, so “natural” or “essential-oil-only” products are very much within scope often more so than lightly fragranced ones.

The thresholds: when you must declare

Declaration is triggered by concentration. A listed fragrance allergen must be named individually when it is present above 0.001% (10 ppm) in leave-on products and above 0.01% (100 ppm) in rinse-off products. Below those thresholds, the allergen does not need separate declaration and remains part of “Parfum”. The leave-on threshold is ten times stricter than the rinse-off one, reflecting that leave-on products stay on the skin.

To apply these thresholds you need to know how much of each allergen your fragrance or essential oils contain information that comes from your fragrance supplier's allergen declaration or IFRA documentation. Without that data you cannot work out what to declare, which is why gathering it is an essential early step rather than a label-stage afterthought.

It is worth stressing that these are concentrations in the finished product, not in the fragrance itself. A fragrance might be, say, 40% limonene, but if it makes up only a small fraction of your formula, the limonene concentration in the finished product is far lower and it is that final figure that you compare against the threshold. Doing this arithmetic correctly is the difference between a compliant declaration and either over-declaring harmlessly or, more seriously, missing an allergen you were required to name.

The expanded EU allergen list

For years the list of individually labelled fragrance allergens stood at 26 entries. That has changed. Under Regulation (EU) 2023/1545, the EU significantly expanded the list of fragrance allergens that must be declared, adding many more substances and refining some existing entries. Products on the EU market need to declare against this expanded list, with transition periods allowing time to update formulations and labels before older labelling can no longer be placed on the market or made available.

Because these transition dates and the precise list matter, EU sellers should check the current requirements rather than rely on the old set of 26. The UK has its own regulatory process and may align differently, so a product sold in both markets should be checked against each. Keeping up with this change is exactly the kind of ongoing task a Responsible Person handles see RP obligations.

How to show allergens on the label

Declared allergens appear within the ingredient list, using their INCI names, alongside your other ingredients and positioned according to their concentration. They are not listed in a separate “allergen” box; they sit in the main “Ingredients” list. So a label might show “…Parfum, Linalool, Limonene, Citronellol…”, where those named allergens are the declarable ones present above threshold and the remainder of the fragrance stays under “Parfum”.

Order still follows the usual rules of descending weight, with the 1% rule applying to the many minor entries. The allergens simply take their proper place among the ingredients. Getting both the identification and the placement right is what makes the declaration compliant.

Common allergen labelling mistakes

The biggest mistake is assuming natural products are exempt they are not, and essential oil heavy products often have the most to declare. The second is labelling against the old list of 26 when selling into the EU, missing the newly added substances. The third is guessing: declaring a generic set of allergens without supplier data, which can be both wrong and incomplete. And the fourth is forgetting that the leave on and rinse off thresholds differ, so a fragrance fine in a wash-off product may need extra declarations in a leave on one.

All of these come down to the same root: not having, or not using, accurate allergen data for your fragrance. With that data in hand, declaration becomes a calculation rather than a guess, and our allergen review exists precisely to provide it.

A practical example

Suppose you make a leave-on body oil scented with a citrus and lavender essential-oil blend. Your supplier's documentation tells you the blend contains limonene, linalool and citronellol, among others, and gives the percentage of each in the blend. Knowing how much of the blend you add to the oil, you can calculate the concentration of each allergen in the finished product and compare it against the 0.001% leave-on threshold. Those that exceed it say limonene and linalool must be named individually in the ingredient list; those below stay within “Parfum”.

Now imagine the same blend used at the same level in a rinse-off shower gel. Here the higher 0.01% threshold applies, so fewer of the allergens may need naming, even though the fragrance is identical. This is exactly why the same fragrance can produce different allergen declarations in different products, and why you cannot simply copy one product's allergen list onto another. The calculation has to be redone whenever the product type or the fragrance level changes.

Allergen labelling checklist

• Obtain allergen data for every fragrance and essential oil.

• Apply the 0.001% leave-on / 0.01% rinse-off thresholds.

• Declare against the current (expanded) EU list for EU sales.

• Check the UK requirements separately for GB sales.

• Show allergens by INCI name within the ingredient list.

• Re-check when you change fragrance, supplier or product type.

Frequently asked questions

Which fragrance allergens must be declared on cosmetics?

A defined list of fragrance allergens must be named individually when present above threshold. The EU list was significantly expanded under Regulation (EU) 2023/1545, beyond the previous 26 substances.

At what level do I have to declare a fragrance allergen?

Above 0.001% (10 ppm) in leave-on products and above 0.01% (100 ppm) in rinse-off products. Below these levels the allergen stays within 'Parfum'.

Do natural and essential-oil products need allergen declarations?

Yes — often more than synthetic ones. Essential oils are rich natural sources of regulated fragrance allergens, so they are firmly within scope.

Where do allergens go on the label?

Within the main ingredient list by their INCI names, positioned by concentration not in a separate allergen box.

Is the UK list the same as the EU's?

Not necessarily. The EU expanded its list under Regulation (EU) 2023/1545, and the UK runs its own process, so products sold in both markets should be checked against each.

How do I know how much of an allergen is in my product?

From your fragrance supplier's allergen declaration or IFRA documentation, which states the allergen content of the fragrance or essential oil. You then scale that by how much fragrance is in the finished formula to get the final concentration.

Do I need to redo allergen declarations for every product?

Yes. Because the thresholds differ for leave on and rinse off and depend on the fragrance level, the same blend can produce different declarations in different products. The calculation must be repeated whenever the product type or fragrance dose changes.

References: Regulation (EC) No 1223/2009, Article 19 and Annex III; Regulation (EU) 2023/1545; IFRA Standards; UK Cosmetics Regulation as retained. General information only, not legal advice.