Korean Sunscreens: Why the Filters Are Different

Korean sunscreens often contain ultraviolet filters that are not sold in the United States, because the two countries file sunscreen under different bodies of law. The United States regulates it as an over-the-counter drug. Korea regulates it as a functional cosmetic. That one difference explains the filter list, the UVA label, and most of the texture gap.

None of this is about national talent for chemistry. It is about which agency has to say yes, and what it needs to see first.

What makes Korean sunscreen different from American sunscreen?

Three things, in order of importance.

First, the pool of legal filters is larger. Second, the UVA label reports a measured grade instead of a pass or fail mark. Third, filter choice drives formulation, so a wider pool produces a wider range of finishes.

Everything else people notice follows from those three. The thinner film. The absence of white cast. The way it sits under makeup. It is one case of a pattern we trace in Korean versus Western skincare. Different regulatory categories produce different product cultures.

One disclosure before going further. re:tones does not make or sell sunscreen. This is a regulatory explainer, not a pitch.

Why the US ultraviolet filter list barely moved for two decades

In the United States, a sunscreen is a drug. The labeling rule at 21 CFR 201.327 applies to products containing 16 named active ingredients, among them avobenzone, homosalate, octinoxate, octisalate, octocrylene, oxybenzone, titanium dioxide, and zinc oxide.

A 2024 review of ultraviolet filters counted those 16 US filters against 29 in Australia and 30 in the European Union. The same review reported that no new ultraviolet filter had been approved in the United States since 1998.

The reason is structural. A drug ingredient has to be shown generally recognized as safe and effective before it can be used. That is a heavy evidentiary lift for a molecule already sold elsewhere for years.

A 2025 review of the US framework argued that the system has not kept pace with filters used internationally. It named bemotrizinol, bisoctrizole, drometrizole trisiloxane, and terephthalylidene dicamphor sulfonic acid as examples available abroad but not domestically.

The evidence bar is genuine, not bureaucratic theater. Agency studies showed that organic ultraviolet filters are systemically absorbed during routine sunscreen use, with no evidence to date of associated negative health effects. The same review notes that concerns about coral bleaching led several localities to ban certain organic filters. FDA's 2019 proposed rule, published to comply with the law as amended by the Sunscreen Innovation Act, described the conditions under which it proposed that monograph sunscreens are safe and effective.

How Korea regulates sunscreen as a functional cosmetic

Korea runs cosmetics under the Cosmetics Act. A 2018 review of international testing requirements notes that the Ministry of Food and Drug Safety upholds that act and enforces testing requirements set forth in a Regulation on the Examination of Functional Cosmetics.

Functional cosmetics are the category between an ordinary cosmetic and a drug. A 2025 review of cosmetics regulation reports that in Japan and Korea, functional cosmetics require separate approval. The same review describes Korea as working from negative and restricted ingredient lists.

Sun protection belongs there too. One Korean materials study opens by describing ultraviolet protection cosmetics, meaning sunscreens, as functional cosmetics.

So the burden is real but differently shaped. A product must be examined and its claim substantiated. The permitted ingredient lists are revised on Korea's own schedule, not through a US proceeding on whether a molecule is generally recognized as safe and effective.

That regulatory position is an underdiscussed part of what K-beauty actually is.

SPF vs PA vs UVA-PF: what each number measures

These three are not competing scales. They measure different things.

SPF measures protection against ultraviolet B and the sunburn it causes. It is measured in vivo, with product applied at 2 milligrams per square centimeter, per the FDA test method. SPF says almost nothing about ultraviolet A.

UVA-PF is the ultraviolet A protection factor, the actual measured number. The standard in vivo endpoint is persistent pigment darkening, or PPD. A review of the competing protocols found that CEN 2006 and FDA 2007 both recommended the PPD method. The same review notes that ISO 24443 aligns an in vitro measurement to PPD, while the FDA 2011 approach uses critical wavelength instead.

PA is not a measurement. It is a label band built on one. PA stands for Protection Grade of UVA. The Japan Cosmetic Industry Association introduced it, running from PA+ at the low end to PA++++ at the high end. The grades are assigned from the in vivo PPD result. A 2026 regulatory review describes the system as developed domestically in Japan and now widely used in Asian markets. Korean labels carry it.

That same review sets out the grades this way.

PA grade	Stated level of UVA protection
PA+	Some UVA protection
PA++	Moderate UVA protection
PA+++	High UVA protection
PA++++	Very high UVA protection

Source: Global Perspectives on Regional Sun Protection Factor Requirements, 2026.

The useful framing came from a 2009 paper on labeling confusion. SPF is an indication of the quantity of protection, while the degree of UVA protection determines the quality of the overall protection. A high SPF with weak ultraviolet A coverage is a lopsided product.

How the three labeling systems compare

	United States	European Union	Korea and Japan
Legal category	Over-the-counter drug	Cosmetic	Functional cosmetic (Korea), cosmetic (Japan)
Filters permitted	16 named in the labeling rule	30 reported in a 2024 count	Set by each regulator's own ingredient lists
UVB label	SPF	SPF	SPF
UVA label	Broad Spectrum, pass or fail	Protection category tied to a ratio rule	PA+ through PA++++
UVA basis	Mean critical wavelength of 370 nm or greater	UVA-PF of at least one third of the labeled SPF	Measured UVA-PF, PPD endpoint

The European ratio rule is worth pausing on. A 2026 regulatory review states that European Union guidance requires the UVA protection factor to be at least one third of the labeled SPF, assessed by a validated in vitro method. That ties ultraviolet A coverage to the SPF on the front of the bottle. A US Broad Spectrum mark does not, because it is a threshold that a product either clears or fails.

There is a second gap. A 2021 review of sunscreens and photoaging noted a paucity of US-approved filters covering long ultraviolet A above 370 nm, and none covering visible light. Ultraviolet A is the band most associated with cumulative dermal damage, which is one strand of what causes skin aging. Visible light matters mostly for pigment, a distinction that also runs through melasma versus general hyperpigmentation.

How to read a Korean sunscreen label

A Korean front label usually carries two numbers, not one. SPF is the ultraviolet B figure. PA is the ultraviolet A grade.

Read them as a pair. SPF 50+ with PA++ is not the same product as SPF 50+ with PA++++, even though the front number matches. The second one was graded higher on the PPD test.

The plus signs are ordinal, not arithmetic. PA++++ is not twice PA++. Each step up represents a higher measured protection factor band, and the top band is open ended.

Ignore the marketing vocabulary printed around them. Terms like moisture, tone up, and cushion describe the base, not the protection. The protection lives entirely in the SPF value, the PA grade, and the ingredient list.

Why filter chemistry changes the texture

Texture is not a styling decision made after the fact. Formulation guidance is blunt about the order of operations. The selection of ultraviolet filters is the first key decision, and it constrains later choices. Sensory feel is treated as a development target alongside efficacy and cost.

Two consequences follow.

Filters differ in how much ultraviolet they absorb per unit weight. They also differ in where across the spectrum they absorb. Hitting a target SPF and a target UVA-PF with a short list means using more total filter, or leaning harder on mineral filters. Both add weight to the film.

Mineral filters carry a visible penalty. A review of zinc oxide and titanium dioxide notes that at nanoparticle scale these filters are much less visible after application, which increases their cosmetic acceptability. The same review notes that zinc oxide has a broad ultraviolet A and B absorption curve, while titanium dioxide provides better ultraviolet B protection. Reach for coverage with minerals alone and the cast has to go somewhere.

A longer filter list gives a formulator more ways to hit the same numbers with a lighter film. That is the whole texture story. It is not a secret ingredient. It is arithmetic performed under a different rulebook.

Where the product lands in a routine is a separate question, covered in our note on skincare routine order. Sun exposure after any procedure that disturbs the skin surface has its own considerations, which we treat separately in our note on sun exposure after at-home treatments.

What changed in 2026

The US list is no longer completely frozen. In June 2026 FDA announced the availability of a final administrative order amending OTC Monograph M020. The order adds bemotrizinol at concentrations up to 6 percent as a sunscreen active ingredient. A sunscreen containing it is generally recognized as safe and effective if it meets the amended monograph conditions.

Bemotrizinol is one of the filters the 2025 review had flagged as available internationally but not domestically. The final order was issued in response to an over-the-counter monograph order request, the process that the same review had noted may provide a pathway to modernizing US sunscreen regulation.

What this does not tell you is when reformulated products appear on shelves, or which other filters follow. An order permits an ingredient. It does not schedule anyone's product development.

The number that matters more than the label

Every rating on every bottle assumes a film thickness almost nobody applies.

SPF testing applies 2 milligrams per square centimeter. A Brazilian study tested two sunscreens at 2, 1.5, 1.0, and 0.5 milligrams per square centimeter. SPF fell significantly as the amount dropped, and the correlation between labeled SPF and applied amount grew exponentially.

Ultraviolet A behaves the same way. A Korean study comparing pigment darkening endpoints noted that only about a quarter of the recommended quantity is used during daily activities. It found an exponential relationship between the amount of sunscreen applied and the UVA-PF.

So a PA++++ grade describes a film applied at test thickness. Thinner film, lower real grade. Choosing between regulatory systems is a smaller decision than choosing to apply enough of whichever bottle you already own.

For how we read and cite published research across this journal, see our science page.

FAQ

Is Korean sunscreen better than American sunscreen?

Not automatically. Korean products draw on a larger filter pool, which makes lighter textures and measured UVA grades easier to achieve. A well formulated US sunscreen applied properly still protects. The honest summary is that Korea offers more formulation options and a more informative UVA label, not that every Korean bottle outperforms every American one.

What does PA++++ actually mean?

PA stands for Protection Grade of UVA. The scale runs from PA+ to PA++++ and is assigned from a measured ultraviolet A protection factor using the persistent pigment darkening method. A 2026 regional review describes PA++++ as very high UVA protection. It is a band, not a precise number, and it assumes the tested application thickness.

Why are most of those ultraviolet filters still missing from American sunscreens?

The United States classifies sunscreen as a drug. Each active ingredient must be shown generally recognized as safe and effective before use. That process is slow and evidence heavy. Korea and the European Union regulate sunscreen through cosmetic frameworks with a different review route. FDA added bemotrizinol to its sunscreen monograph in June 2026, but other filters used abroad are still outside it.

Is Broad Spectrum the same as PA+++?

No. Broad Spectrum is a pass or fail mark. A US product passes when its mean critical wavelength reaches 370 nm or greater, and the label reports nothing beyond pass. PA reports a graded band derived from a measured protection factor. Two Broad Spectrum products can differ substantially in ultraviolet A performance while carrying identical front labels.

Are Korean sunscreens safe if FDA has not reviewed most of their filters?

FDA added bemotrizinol to OTC Monograph M020 in June 2026. Most other filters used abroad have not been evaluated under the US drug monograph, which is a jurisdictional fact rather than a safety verdict. Those filters were reviewed by other regulators under their own frameworks. If you have contact allergy, photosensitivity, or a diagnosed skin condition, take the ingredient list to a board certified dermatologist.

How much sunscreen should I actually apply?

Testing standards use 2 milligrams per square centimeter, and studies consistently find real use falls well short of it. Applying more of the product you already have moves your real protection further than switching brands or countries. Reapplication matters for the same reason, since the film thins with wear, sweat, and contact.