If you make or sell shampoo bars in the U.S., the first question is whether FDA views your product as a cosmetic or as true soap. Most shampoo bars are cosmetics because they are marketed to cleanse hair and usually contain synthetic detergents or other surfactants. That means they must follow FDA cosmetic labeling rules under the Federal Food, Drug, and Cosmetic Act and the Fair Packaging and Labeling Act.

Is your shampoo bar a “soap” or a cosmetic?

True soap under FDA’s narrow definition must be made mainly of alkali salts of fatty acids - for example, saponified oils - and must get its cleansing power from those compounds. It also must be labeled and sold only as soap. If you call the product a “shampoo bar,” make hair-cleansing or conditioning claims, or use synthetic detergents, FDA generally regulates it as a cosmetic. Some bars can be both a soap and a cosmetic if they make cosmetic claims.

Core FDA labeling requirements for shampoo bars

Assuming your shampoo bar is a cosmetic, the label must include these elements:

  • Statement of identity: The common or usual name of the product, such as “Shampoo Bar,” or a clear description of what it does.
  • Net quantity of contents: The weight of the bar, stated accurately. A typical format is “Net Wt. 3.5 oz (99 g).” It must appear on the principal display panel.
  • Name and place of business: The name and address of the manufacturer, packer, or distributor. The address must include street address, city, state, and ZIP code. If the product is made for another company, use wording such as “Manufactured for” or “Distributed by.”
  • Ingredient declaration: A complete list of ingredients in descending order of concentration, preceded by the word “Ingredients.”

How to write the ingredient list

  • List ingredients by descending order of predominance in the formula.
  • Use standard cosmetic ingredient names - typically INCI names are best.
  • Ingredients present at 1% or less may be listed in any order after the ingredients above 1%.
  • Color additives may be listed after the other ingredients.
  • Fragrance or flavor may simply be listed as “fragrance” or “flavor.”

Warning and safe-use statements

FDA requires labeling to include any directions or warnings needed for safe use. For a shampoo bar, that often means a caution such as “Avoid contact with eyes. If contact occurs, rinse thoroughly with water” or “For external use only.” Clear directions for use on hair may also be important, especially if the bar could be confused with ordinary soap.

When a shampoo bar is also a drug

If you add anti-dandruff ingredients, make claims about treating dandruff, psoriasis, hair loss, or scalp conditions, or include ingredients intended to treat or prevent disease, FDA may regulate the product as a drug. In that case, you must follow drug labeling requirements, typically including a “Drug Facts” panel, active ingredients, uses, warnings, and directions. Most ordinary cleansing shampoo bars are cosmetics, but disease-related claims change the regulatory picture.

Labeling mistakes to avoid

  • Missing the net weight or only stating it in ounces without a metric equivalent.
  • Not listing ingredients in proper descending order.
  • Making drug-like claims such as “treats eczema” or “prevents hair loss” without meeting drug requirements.
  • Assuming handmade, small-batch, or natural products are exempt from labeling requirements - FDA does not have a general small-batch exemption for cosmetic labeling.

FDA labeling rules are detailed and can depend on your exact formula and marketing claims. If you are unsure about your shampoo bar, consult FDA’s cosmetic labeling regulations in 21 CFR Part 701 or work with a cosmetic regulatory specialist or attorney.