The most important thing to understand about American sunscreen is categorical rather than technical. In the United Kingdom and the European Union, sunscreen is a cosmetic product. In the United States it is an over the counter drug. Everything else follows from that.
What being a drug means
Over the counter drugs in the United States are regulated by the Food and Drug Administration, historically through a monograph system that sets out which active ingredients may be used, at what concentrations, for what indications, with what labelling. A product that conforms to the monograph can be marketed without individual pre approval. A new active ingredient outside the monograph faces a far more demanding route.
The practical effects are visible on the pack. American sunscreen carries a Drug Facts panel listing active ingredients with their percentage concentrations, followed by uses, warnings, directions and inactive ingredients. That is a genuinely useful document, and it is more explicit than a European ingredients list, where filters appear in the general INCI list without concentrations.
It also has an effect that is much discussed: because adding a new filter requires clearing a drug approval pathway, the American list of permitted ultraviolet filters has changed slowly, and some filters used routinely in Europe and Asia are not available there. That is a regulatory pathway question rather than a safety verdict, and we do not draw conclusions from it in either direction.
The 2011 labelling rule and what it removed
The Food and Drug Administration's sunscreen labelling rule, which took effect in the early 2010s, did several things that a British reader will recognise from the European position.
- It prohibited waterproof and sweatproof as sunscreen claims, for the same reason Europe does not permit waterproof: they are absolute and cannot be substantiated.
- It prohibited sunblock.
- It required water resistance, where claimed, to be stated as a tested duration in minutes, either forty or eighty.
- It defined Broad Spectrum as a designation earned under a specified test rather than a free descriptor.
- It required a warning on products that are not broad spectrum or are below a defined factor, stating that the product has not been shown to help prevent skin cancer or early skin ageing.
That last requirement has no European equivalent and is one of the more informative things on an American pack.
Water resistance in minutes
Stating the duration is a better piece of communication than a category, because it puts the limit of the claim on the front of the pack where the reader can see it. A person holding a pack that says water resistant for eighty minutes is being told, in plain English, that the tested boundary is eighty minutes.
What it shares with the European approach is the underlying limitation. It is an immersion procedure. It does not simulate abrasion, towelling, salt water or your session. Our note on what water resistant certifies applies in spirit to both regimes.
Reading a US pack in the UK
Broad Spectrum SPF 50+, Water Resistant (80 minutes)
What it certifies
On a United States pack: that the product passed the Food and Drug Administration broad spectrum test, that its sun protection factor is at the top of the labelled range, and that it retained its labelled factor through the eighty minute water immersion procedure the agency specifies. The duration is required to be stated, which makes the boundary of the claim explicit.
What it does not
It does not translate directly into UK or EU terms, because the underlying procedures and the labelling conventions differ. There is no UVA in a circle mark and no star rating. And, as everywhere, none of it addresses abrasion or towelling.
Three things to check if you find yourself holding one.
1. Is it Broad Spectrum?
If not, it has passed no ultraviolet A test at all under the American system, and there is no circle mark to fall back on.
2. What is the stated water resistance?
Forty minutes, eighty minutes or no claim. Read it as the tested boundary.
3. What is in the Drug Facts panel?
The active ingredients and their concentrations are stated, which is more information than a European pack gives you. If a specific filter matters to you, this is where to look.
Why the numbers are not directly comparable
It is tempting to assume that a factor is a factor everywhere. Broadly, the sun protection factor concept is shared, and the international test methods have converged considerably. But the procedures, the permitted filters, the ultraviolet A criteria and the labelling conventions all differ, so treating an American pack as if it were a British one is a small but real error. Our note on buying sunscreen abroad sets out what to do about it.
The permitted filter list, and why it is different
The most discussed practical difference between the American and European positions is the list of ultraviolet filters available to formulators. Because a filter in the United States is a drug active, adding a new one means clearing a drug approval pathway rather than being added to a permitted annex. That pathway is slower and more demanding, and the consequence is that the American list has changed less over the last two decades than the European one.
It is important to be careful about what this does and does not mean. It does not mean American products are worse, and it does not mean the filters unavailable there are unsafe, or that they are safe. It is a statement about regulatory routes, not about performance or toxicology, and anyone drawing a stronger conclusion is going beyond what the fact supports. We take no position on any individual filter and publish no safety opinions, which is set out in our editorial standards.
What it means for you at a shelf is narrow and useful. If you have found a filter system that suits your skin in the UK, you may not find its equivalent on an American pack, and the reverse is also true. That is a reason to read the Drug Facts panel rather than to assume equivalence.
The warning that has no European equivalent
The American labelling rule requires products that are not broad spectrum, or that fall below a defined factor, to carry a statement that the product has not been shown to help prevent skin cancer or early skin ageing. It appears in the Drug Facts panel, in the same typography as everything else, with no marketing softening.
There is nothing like it on a UK or EU pack. The European approach relies instead on the UVA in a circle mark being present or absent, which communicates by omission rather than by warning. Both approaches convey a similar underlying idea. The American one is louder, and for a shopper in a hurry, louder is arguably better.
What is not verifiable
We do not compare regimes on the basis of which produces better products, because that would require testing we have not done. We do not publish filter safety opinions. What we can do is set out what each system requires on the label, which is public, checkable and the thing a reader actually needs at the point of purchase.
Back to the UK
For a British reader, the useful takeaway is that the American system is more explicit in two places, concentrations and water resistance duration, and less explicit in one, ultraviolet A indication at a glance. Neither system removes the need to apply enough and to reapply. Our note on reapplication is regime independent.