How we rate · 🤧 Allergens
Sunscreen and skin allergies, which ingredients raise the risk
If a sunscreen leaves your skin itchy, bumpy or red a day or two after you put it on, that's often not the UV filters, it's the supporting cast. Fragrance, botanical oils and a handful of preservatives are the classic contact allergens, and they show up in sunscreen as often as in any cream. Most people wear them with no trouble at all; but if your skin is sensitization-prone, knowing which ingredients carry the risk lets you steer around them. RateMySPF reads the full INCI list of every sunscreen in our catalog and scores this allergy risk, so below we'll walk through exactly what drives it, and point to real products that show each factor in action.
TL;DR: the ingredients that drive allergens
- Fragrance / Parfum: the single most common cosmetic contact allergen, one entry can hide dozens of aroma chemicals you can't see
- Methylisothiazolinone (MI): Allergen of the Year 2013 after an epidemic of reactions, our single largest penalty in this axis
- Methylchloroisothiazolinone (MCI): MI's partner in the old 'Kathon' blend, close behind, and the two are often listed side by side
- Eugenol: a moderate declared EU fragrance allergen, clove-like aroma chemical that earns a middling penalty
- Citral: moderate declared allergen, lemony terpene common in citrus oils
- Geraniol: moderate declared allergen from rose and citronella oils
- Citronellol: moderate declared allergen, rosy terpene we tier in the middle
- Coumarin: declared EU fragrance allergen with a hay-like, vanilla scent
- Limonene & Linalool: the ubiquitous weak pair, mild on their own, mainly a problem once oxidised, so the lightest penalty
- Lanolin: the wool-derived 'great deceiver', an erratic, mild sensitizer we flag gently in balm-style sticks
What "allergenic" actually means here
This axis is about contact allergy, true skin sensitization, where your immune system learns to react to a specific molecule and then flares every time it meets that molecule again. It's a delayed, immune reaction, and it's a different thing from the instant burn of sunscreen in your eyes (that's our separate eye-sting axis) and from plain irritation. The same fragrance can sting one person's eyes and sensitize another's skin, but the mechanisms, and the ingredients that matter most, aren't the same.
Two facts shape the whole score. First, the worst offenders aren't the UV filters at all, they're fragrance, the botanical oils that carry the same fragrant terpenes, and a small group of preservatives, with methylisothiazolinone (MI) the standout of the last decade. Second, and this is the big difference from eye sting, mineral filters don't save you here. An allergen reaches your skin no matter what filter system sits alongside it, so a zinc-oxide formula loaded with fragrance is every bit as risky as a chemical one. We give no mineral discount on this axis.
One caveat up front, and we mean it: this is a propensity score, never a verdict. The overwhelming majority of people tolerate every ingredient below perfectly well. A high score means "this formula carries a lot of known allergens, so it's a poor bet for sensitization-prone skin", not "this will give you a rash". Every sunscreen starts at a clean 100 and loses points for the ingredients below; the more allergens it stacks, and the more potent they are, the lower it lands. The levels run low, medium and high.
▲ Fragrance: the single biggest lever
Raises risk
Fragrance is the most common cause of cosmetic contact allergy, full stop, so a flat Fragrance or Parfum on the label is the first thing we penalise. A single "Fragrance" entry can be a blend of dozens of aroma chemicals, any of which a sensitized person might react to, so we apply a fixed penalty whenever it appears, regardless of where it sits in the list.
On its own, fragrance moves a product from a clean zero into the low tier, not catastrophe, just a measurable risk. It's when fragrance travels with declared allergens, essential oils or sensitizing preservatives that scores really fall, and that stacking is what the rest of these factors capture. The beachy-scented drugstore classics are the obvious place this starts.
Fragranced everyday formats, note that a bare "Fragrance" with little else declared still lands in the low tier:
- Fragrance
- Opaque "Fragrance", hidden allergens that can't be checked from the label
- Photoallergen-tail UV filters (Octocrylene)
- Fragrance
- Opaque "Fragrance", hidden allergens that can't be checked from the label
- 2 declared fragrance allergens
▲ The EU-26 declared allergens, tiered by potency
Raises risk
European labels are required to spell out 26 specific fragrance allergens by name when they're present above a threshold, the linalool, limonene, citronellol, geraniol, citral, coumarin, eugenol family you'll spot at the end of many INCI lists. These aren't all equally risky, so we don't score them equally. We tier them: strong sensitizers like cinnamal, isoeugenol and hydroxycitronellal carry the heaviest penalty; moderate ones like geraniol, citronellol, citral and eugenol a middling one; and the weak, ubiquitous pair limonene and linalool, which are mild and only really problematic once oxidised, the lightest. The more named allergens a formula declares, the more the penalty builds, up to a cap.
Two of the historic EU-26, Lilial (Butylphenyl Methylpropional) and Lyral (Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde), are now outright banned in the EU for safety. We rate them in the strong tier and flag them specifically when they turn up, almost always in older or grey-market stock that predates the ban.
A natural-leaning brand can rack up a startling count. Apivita's Bee Radiant day cream declares eleven of these allergens, enough to hit the block cap on its own, and the list includes banned Lilial; Dr. Hauschka's face sun cream likewise declares eleven. Even a luxury fluid like La Mer's lists five.
Products whose own labels declare a long list of named fragrance allergens, honest disclosure, but a lot to react to:
- 11 declared fragrance allergens; EU-banned: Butylphenyl Methylpropional
- Fragrance
- Sensitizers from 4 different categories
- 11 declared fragrance allergens
- Fragrance
- Sensitizers from 3 different categories
- Fragrance
- 5 declared fragrance allergens
- Photoallergen-tail UV filters (Benzophenone-3, Octocrylene)
▲ Essential oils: "natural" doesn't mean hypoallergenic
Raises risk
Here's the trap with "fragrance-free, scented only with natural essential oils": the molecules that make a contact allergen are the same whether they arrive in a synthetic fragrance or in cold-pressed lavender oil. Citrus, lavender, tea tree, mint, eucalyptus, geranium, ylang-ylang, clove and their relatives are rich in exactly the terpenes that sensitize skin, often the very limonene and linalool the EU makes you declare. So we rate the oil forms of these allergenic plant genera directly, by name.
We weight them by position, because an oil high in the list is present in far more than a trace at the end, and we stack multiple oils up to a cap. We're careful to exclude bland carrier seed oils (sunflower, jojoba and the like), which aren't fragrant or allergenic, it's the fragrant essential oils we're after. A "natural" men's moisturiser like ManCave's, which pours in lime, eucalyptus, lavandin, marjoram, rosemary and thyme oils, hits the oil cap by itself.
Botanically-scented formulas carrying several allergenic essential oils:
- Fragrance
- 6 declared fragrance allergens
- Essential oils (Citrus Aurantifolia Oil, Eucalyptus Globulus Leaf Oil, Lavandula Hybrida Oil, …)
- Fragrance
- 4 declared fragrance allergens
- Essential oils (Anthemis Nobilis Flower Oil, Cinnamomum Camphora Linalloliferum Leaf Oil, Pelargonium Graveolens Flower Oil)
▲ Sensitizing preservatives: the MI problem
Raises risk
Every water-based cream needs a preservative, and most are perfectly gentle, but a few are notorious sensitizers, and one in particular touched off a contact-allergy epidemic. Methylisothiazolinone (MI) was named Allergen of the Year in 2013 after rates of reaction shot up; we give it the single largest penalty in this whole axis. Its cousin methylchloroisothiazolinone (MCI), the two together are the old "Kathon" blend, is close behind, and the two are often listed side by side.
Below those sit the formaldehyde releasers, DMDM hydantoin, the ureas (diazolidinyl, imidazolidinyl), quaternium-15, bronopol, which slowly shed tiny amounts of formaldehyde, itself a known allergen; plus formaldehyde proper, methyldibromo glutaronitrile, the BIT/OIT isothiazolinones and a few others. Each carries a flat penalty scaled to how problematic it is, and they add up to a cap.
This is where some very mainstream products stumble. Several Neutrogena Ultra Sheer lotions still list MI; Australian Gold's bronzer lotion does too; and the worst case we see is a formula that pairs MI and MCI, like Belo's whitening creams, which take the full preservative penalty.
Formulas relying on the isothiazolinone preservatives MI / MCI:
- Sensitizing preservatives (Methylisothiazolinone, Methylchloroisothiazolinone)
- Fragrance
- Opaque "Fragrance", hidden allergens that can't be checked from the label
- Fragrance
- Sensitizing preservatives (Methylisothiazolinone)
- Opaque "Fragrance", hidden allergens that can't be checked from the label
- Fragrance
- Sensitizing preservatives (Methylisothiazolinone)
- Opaque "Fragrance", hidden allergens that can't be checked from the label
▲ Photoallergen UV filters: the sensitizing tail
Raises risk
A few UV filters have a genuine contact-allergy track record of their own, and since this is a sunscreen they're always present, so we account for them. Benzophenone-3 (oxybenzone) was Allergen of the Year in 2014 and carries the biggest filter penalty here; benzophenone-4 and 4-methylbenzylidene camphor follow, with octocrylene and Padimate O on a lighter tail. These are photoallergens, the reaction typically needs sun exposure to trigger, which is exactly the condition a sunscreen is worn in.
We keep these penalties deliberately modest. Octocrylene in particular shows up in a third of the catalog and the signal is still emerging, so we don't over-tax it, we trimmed its weight specifically to avoid punishing a huge slice of ordinary products. The filter penalties are a tail on the score, not the main event; fragrance and preservatives do the heavy lifting. Note, too, that this is purely the skin-sensitization angle, octocrylene's separate role in eye stinging lives on our eye-sting axis, not here.
Sunscreens whose filter system itself carries oxybenzone (BP-3):
- Fragrance
- 5 declared fragrance allergens
- Photoallergen-tail UV filters (Benzophenone-3, Octocrylene)
- Fragrance
- Sensitizing preservatives (Methylisothiazolinone)
- Opaque "Fragrance", hidden allergens that can't be checked from the label
▲ Lanolin and propolis: the bee-and-wool allergens
Raises risk
Two more classic sensitizers earn their own small penalty. Lanolin, the wool-derived emollient beloved of lip balms and rich creams, is an old dermatology fixture, nicknamed the "great deceiver" because reactions are erratic. It's a weak sensitizer on intact skin, so we rate it gently, but it earns a flag. Propolis (bee glue), common in natural and Korean formulas, is a stronger and rising contact allergen and carries a larger penalty.
These rarely sink a score alone, but they push a borderline formula over a tier line and, more importantly, they're a useful heads-up for anyone with a known wool or bee allergy. Dr. Hauschka's sun creams use propolis; many balm-style SPF sticks lean on lanolin, as Blistex's repair balm does.
Formulas carrying lanolin or propolis:
- 11 declared fragrance allergens
- Fragrance
- Sensitizers from 3 different categories
- Fragrance
- Sensitizers from 4 different categories
- Opaque "Fragrance", hidden allergens that can't be checked from the label
▲ Pricing the opacity of an undisclosed "Fragrance"
Raises risk
Here's a subtlety we think a lot of scorers get wrong. A European label that lists "Fragrance (Parfum), Linalool, Limonene, Citronellol…" is being honest, it's telling you precisely which allergens are inside. A US or budget label that just says "Fragrance" and stops is being opaque: the same allergens may be in there, you simply can't see them. If we only counted declared allergens, the honest label would score worse than the opaque one, punishing disclosure, which is exactly backwards.
So we price the opacity. When a product lists "Fragrance" but declares few or no specific allergens, we top its fragrance-related penalty up to a floor, the minimum a barely-disclosed mix would carry, so a vague "Fragrance" can no longer score better than an itemised one. Crucially, a label that already declares allergens past that floor gets no top-up: honest disclosure is never penalised. This is why Sun Bum's "Fragrance"-only lotion takes a sizeable opacity charge, while a transparent EU label that lists its allergens outright doesn't, it's already told you the truth.
Opaque "Fragrance"-only labels that pick up the disclosure top-up:
- Fragrance
- Opaque "Fragrance", hidden allergens that can't be checked from the label
- Photoallergen-tail UV filters (Octocrylene)
- Fragrance
- Sensitizing preservatives (Methylisothiazolinone)
- Opaque "Fragrance", hidden allergens that can't be checked from the label
▲ Polysensitization: the kitchen-sink penalty
Raises risk
The factors above each cover one class of allergen. But a formula that draws from many classes at once, fragrance AND declared allergens AND essential oils AND a sensitizing preservative, is riskier than the sum of its parts: it gives sensitization-prone skin more independent ways to react, and someone reactive to one class is statistically more likely to react to others. So when a product carries allergens from three or more separate classes, we add a polysensitization bonus penalty on top, scaling up as the classes pile on.
This is the device that separates a true high from a merely fragranced low. A product with only "Fragrance" stays low; one like Apivita's day cream, fragrance, eleven declared allergens, four citrus and rose oils, octocrylene and propolis, allergens from four classes at once, earns the bonus and lands deep in high. We deliberately softened this penalty after external review (the classes already overlap somewhat, so a heavy bonus would double-count), but the kitchen-sink signal still holds.
Kitchen-sink formulas drawing allergens from several classes at once:
- 11 declared fragrance allergens; EU-banned: Butylphenyl Methylpropional
- Fragrance
- Sensitizers from 4 different categories
- Sensitizing preservatives (Methylisothiazolinone, Methylchloroisothiazolinone)
- Fragrance
- Opaque "Fragrance", hidden allergens that can't be checked from the label
● What we deliberately don't score
Neutral
Plenty of ingredients have a scary reputation they don't quite earn, and we leave them alone on purpose. Phenoxyethanol is the big one: it's the most common preservative in the whole catalog, and while a true allergy to it exists, it's rare enough that penalising it would flag thousands of perfectly gentle products for almost no real-world benefit. We don't score it. Same for chlorphenesin, and for beeswax and royal jelly (unlike propolis, they're weak sensitizers).
We also give no mineral discount on this axis, worth repeating, because it surprises people coming from our eye-sting scores. There, zinc oxide earns a big break; here it earns nothing, because a mineral filter does nothing to stop a fragrance or preservative from reaching your skin. And a low-but-not-zero score isn't a red flag: a fragrance-free formula whose only ding is a mild preservative like IPBC, EltaMD's UV Clear is a good example, still sits comfortably in the low tier. The goal is to flag genuine allergen load, not to chase every molecule with a Wikipedia page.
▼ What lowers the risk: a clean, fragrance-free base
Lowers risk
There's really only one lever that pulls this score down, and it's the absence of everything above. A fragrance-free formula, no Parfum, no declared allergens, no essential oils, built on a gentle preservative system and free of lanolin and propolis simply has nothing for us to penalise, and scores a clean 100, in the low tier. This is the entire fragrance-free dermatology canon: Vanicream, La Roche-Posay's Anthelios, CeraVe, Avène, plus the better Korean fragrance-free picks like Beauty of Joseon.
Notice that these span both mineral and modern-chemical filters, because, again, the filter type is irrelevant to allergy. What they share is a deliberately bare ingredient list. If your skin reacts easily, "fragrance-free" on the front and a short, recognisable INCI list on the back is the most reliable signal you can use, and it's exactly what a perfect score on this axis reflects.
Fragrance-free formulas that score a clean zero allergen risk:
How to pick a low-allergen sunscreen
If your skin is reactive, the gold standard is simple: choose a fragrance-free sunscreen with a short ingredient list. Fragrance-free beats "unscented" (which can mean masking fragrance was added) and beats "natural" or "essential-oil scented", which carries the same allergenic terpenes as synthetic perfume. Don't rely on mineral vs chemical to make the call, it tells you nothing about allergy here. And when you can, read the actual back-of-pack list rather than the marketing claims; the fragrance-free derm staples above are a safe default.
If you suspect a specific reaction, patch-test before committing: dab a little on the inner forearm once a day for several days and watch for delayed redness or itch, since contact allergy is slow to show. A dermatologist's patch-test panel can pinpoint the exact culprit, very often it turns out to be fragrance or MI, the two we weight most heavily. One genuinely useful tip: a detailed EU-style label that lists its fragrance allergens by name is your friend, not your enemy, it lets you scan for the specific molecule you react to. The label you can't read is the one to be wary of.
Above all, keep the propensity caveat in mind. Most people never react to any of this. If a sunscreen has worn well on your skin for years, the chemistry says you're free to keep using it, this score is a guide for picking something new when your skin has given you reason to be careful, not a reason to throw out what already works.
We rate every sunscreen in our catalog for allergens.
Browse low-allergen sunscreensFrequently asked questions
Can sunscreen cause an allergic reaction?
Yes, though it's uncommon. True contact allergy to sunscreen is most often caused not by the UV filters but by fragrance, allergenic essential oils, or sensitizing preservatives like methylisothiazolinone (MI). A few filters (notably oxybenzone) can act as photoallergens too. Most people tolerate all of these fine, RateMySPF scores the allergen load so sensitization-prone skin can steer around it.
Which sunscreen ingredients are most allergenic?
Fragrance/Parfum is the single most common cosmetic allergen. After that: the preservative MI (and its partner MCI), declared fragrance allergens like cinnamal and isoeugenol, allergenic essential oils (citrus, lavender, tea tree), oxybenzone, and lanolin or propolis. We tier all of these by how potent and well-documented each one is.
Is mineral sunscreen better for allergies?
Not necessarily. Zinc oxide and titanium dioxide are themselves very low-allergy, but a mineral sunscreen can still contain fragrance, essential oils or sensitizing preservatives, and those reach your skin regardless of the filter. That's why this score gives no mineral discount, unlike our eye-sting score. A fragrance-free formula matters far more than mineral vs chemical.
Are 'natural' or essential-oil sunscreens hypoallergenic?
Often the opposite. Essential oils like citrus, lavender, tea tree and ylang-ylang are loaded with the same terpenes (limonene, linalool, geraniol) that the EU makes brands declare as allergens. "Natural fragrance" is still fragrance. We rate the allergenic essential oils by name, weighted by how much is present.
What is methylisothiazolinone and why does it matter?
MI is a preservative that triggered a wave of contact-allergy cases and was named Allergen of the Year in 2013. It carries the largest single penalty in our allergen score. It's often paired with MCI (the old Kathon blend). If your skin reacts to creams, MI is one of the first ingredients worth ruling out.
Why do you penalise a vague 'Fragrance' more than a label that lists allergens?
Because an honest label that itemises its fragrance allergens lets you avoid the specific one you react to, while a bare "Fragrance" hides them. If we only counted declared allergens, the transparent label would unfairly score worse. So we top up the penalty on opaque "Fragrance"-only labels to a floor, and never penalise a label for disclosing more than that floor.
Does a low allergen score mean the sunscreen will give me a rash?
No. This is a propensity score, not a diagnosis. A low score means the formula stacks a lot of known allergens, so it's a poor bet for someone whose skin sensitizes easily, not that it will react on everyone. The large majority of people wear these ingredients with no problem at all.
How can I tell if I'm allergic to my sunscreen?
Contact allergy is delayed, so look for redness, itch or small bumps a day or two after use, often where you applied it most. Patch-test a new product on your inner forearm for several days before full use, and see a dermatologist for a formal patch-test panel if reactions persist, it can identify the exact ingredient, frequently fragrance or MI.
What are the EU-26 fragrance allergens?
They're 26 specific aroma chemicals, linalool, limonene, citronellol, geraniol, citral, coumarin, eugenol and the rest, that EU labels must spell out by name when present above a threshold. We tier them by potency: strong sensitizers like cinnamal and isoeugenol take the heaviest penalty, moderates like geraniol, citral and eugenol a middling one, and the weak pair limonene and linalool the lightest.
Are limonene and linalool bad in sunscreen?
They're the mildest of the declared fragrance allergens, so they get our lightest penalty. Both are ubiquitous terpenes that are only really problematic once oxidised. On their own they're a minor ding, it's when they stack with fragrance, oils and sensitizing preservatives that the score really falls.
Is phenoxyethanol an allergen we should avoid?
We deliberately don't score it. Phenoxyethanol is the most common preservative in the whole catalog, and while a true allergy to it exists, it's rare enough that penalising it would flag thousands of perfectly gentle products for almost no benefit. The preservatives we do weight are MI and MCI, plus the formaldehyde releasers.
Does mineral sunscreen get a lower allergen score?
No, and this is the big difference from our eye-sting axis, where zinc oxide earns a large break. A mineral filter does nothing to stop a fragrance, essential oil or preservative from reaching your skin, so a zinc-oxide formula loaded with fragrance is every bit as risky here as a chemical one. We give no mineral discount on this score.