Is sunscreen an OTC drug or a cosmetic in the US?

In the United States, sunscreens are regulated as OTC drugs by the FDA under 21 CFR Part 352 and the 2019 proposed rule. This means your formulator must work within FDA's approved active ingredients and concentrations, your label must include a Drug Facts panel, and your manufacturer must be an FDA-registered OTC drug facility. This is one reason finding a formulator with OTC experience — easily searchable in the AJ Cosmo Labs app — is critical.