Know whose duty it is
Importing makes it yours.
Buy stock abroad and sell it here, and the UK safety obligations become yours.
A cosmetic placed on the UK market must have a Responsible Person established in the United Kingdom, a Cosmetic Product Safety Report assessing it, and a notification made before it goes on sale. Where a brand or distributor has already done that, a shop selling the product is simply a retailer. Where a shop imports the product itself, that shop becomes the Responsible Person and inherits the whole duty.
This is the single most common gap in small online beauty retail, and it is almost always innocent. Someone finds a product abroad, buys a pallet, lists it, and sells it in good faith with no idea that a safety file and a notification should exist in their name. The products may be perfectly good. The obligation is still unmet, and the person carrying it does not know they are carrying it.
So we treat the question as part of stocking something rather than as paperwork to worry about later, and we will tell any customer which role applies to a given product. The same instinct governs how products are described. A cosmetic presented as treating, curing or preventing a condition is a medicinal product requiring MHRA authorisation, so nothing here treats hair loss, scalp disease or anything else. When someone asks whether a product will fix a condition, the useful answer points them at a clinician.
Importing makes it yours.
Not retrospectively, if asked.
Nothing here treats a condition.
Ingredients, suitability, or who the Responsible Person is. No obligation.