INCI labeling of soap: how to make a label correctly

TL;DR: The INCI list is the mandatory international list of ingredients on the label. Saponified oils are listed as sodium salts (Sodium cocoate, Sodium olivate). Ingredients are listed in descending order of quantity. Allergens in essential oils are listed if they exceed 0.01%. Without the correct INCI, the label is invalid and the sale is illegal.

INCI (International Nomenclature of Cosmetic Ingredients) is an internationally standardized system of names for cosmetic ingredients. If you sell soap as a cosmetic product in the EU, the correct INCI labelling is legally required.

Errors in INCI labelling are one of the most common mistakes made by small manufacturers - either they use common names instead of INCI, allergens are missing or the order of ingredients is wrong. This page will guide you through the complete procedure.

Why is INCI mandatory?

What the law says and why

Regulation (EC) No 1223/2009 of the European Parliament and of the Council on cosmetic products, Article 19, makes it mandatory to indicate ingredients on the label under the INCI name.

Practical reason: The INCI allows consumers and allergists to identify the ingredients regardless of language - the Latin name "Olea europaea fruit oil" is the same in Czech, German and Polish.

How should you proceed step by step?

Step 1: Find the INCI name for each ingredient

Oils and fats - what is stated:

Saponified products - the most important:

After saponification of NaOH with oils, the following are formed fatty acid sodium salts. The INCI name is not "NaOH“ (it is not found in the finished soap), but:

By-products of saponification:

• Glycerin is produced as a natural by-product - INCI: Glycerin
• Water remains in the soap in small quantities - INCI: Aqua

Warning: If you use premium super fat oils added after trace (to make them saponify as little as possible), list these oils by their unsaponified INCI name (Olea europaea fruit oil, Simmondsia chinensis seed oil, etc.).

Additives:

• Sodium chloride (salt): Sodium chloride
• Honey: Mel
• Oat flakes (colloidal): Avena sativa kernel flour
• Activated carbon: Charcoal
• Lavender EO: Lavandula angustifolia oil
• Tea tree EO: Melaleuca alternifolia leaf oil
• Fragrance (FO): parfum

Colorful: Indicate with CI number: "CI 77891″ (titanium dioxide), "CI 77491″ (iron oxide red), etc.

Step 2: What order should the ingredients be in?

What is the correct order?

EU rule: Ingredients shall be listed in descending order of concentration by weight in the finished product.

For CP process soap:

• Mostly: sodium salts of fatty acids (Sodium cocoate, Sodium olivate...) - result of saponification of oils
• Second most: Aqua (water)
• Third: Glycerin (a natural by-product of ~8-12% of total soap)
• Then: superfat oils, additives, EO/FO, dyes

Exception under 1%: Ingredients present at concentrations below 1 % may be listed in any order after those above 1 %.

INCI example for a simple CP soap:

Sodium cocoate, Sodium olivate, Aqua, Glycerin, Sodium ricinoleate, Lavandula angustifolia oil, CI 77891

Step 3: Which allergens do I need to list?

What percentage is the limit for allergens?

EU Regulation 1223/2009 and Regulation (EU) 2023/1490 require fragrance allergens to be indicated on the label if they exceed a certain concentration:

• Wash-off products (rinse-off - soap): Indicate allergens present in concentration above 0,01 % (100 ppm)
• Leave-on products: Indicate above 0,001 %

The most common allergens in EO and FO for soap:

How to count? The FO or EO supplier should provide a list of allergens with the concentrations in their product. Based on this, do the math: if the FO contains 2% linalool and you use the FO at 3% in your soap, then the linalool content of the soap = 0.06% → above the 0.01% limit → you must indicate on the label.

What information must be on the label?

Full list of mandatory data

According to EC Regulation 1223/2009, Article 19:

1. Name and address of the responsible person (manufacturer or importer) in the EU
2. Nominal content at the time of packaging (gram or ml) - for solid soap, weight in grams
3. Date of minimum durability (if ≤ 30 months: "Best used within…“) or PAO symbol (otevřená nádobka s číslem měsíců, pokud > 30 měsíců)
4. Special notice (if any - e.g. "Not suitable for children under 3 years“ for products with high EO concentration)
5. Batch number or references for identification (for saleable products)
6. Functions of the product - if not obvious from the packaging (usually obvious for soap)
7. List of ingredients - must begin with the word "Ingredients:“ (in English) or "Ingredients:“ (in Czech), or INCI previous must be clear

What language on the label?

What applies to the Czech Republic

The label must be in the language of the Member Statewhere the product is sold. For the Czech Republic = Czech. However, the INCI list is an exception - INCI names are Latin/English and do not need to be translated (they are internationally valid).

Example of a label for the Czech Republic:

Name: lavender soap
Producer: Jan Novák, Příkladná 1, 100 00 Praha
Content: 100 g
Date of manufacture: 03/2026, Batch: 001
Best before: 03/2028

Ingredients: Sodium olivate, Sodium cocoate, Aqua, Glycerin, Lavandula angustifolia oil, Linalool**, Limonene**

** Natural part of natural fragrance oil

How to label natural or organic products correctly?

The rules for claiming "natural“ and "organic“

If you use "natural“, "organic“ or "bio“ on the label, strict rules apply:

• There is no uniform EU regulation for "natural“ in cosmetics
• For a certified "organic“ or "natural“ product in the Czech Republic/EU, the COSMOS Natural/Organic certification (Ecocert, BDIH, etc.)
• Non-certified product labelled as "100% natural&#8220may be the subject of a complaint for misleading advertising

Where to find the INCI database?

Freely available resources

• CosIng (EU database): ec.europa.eu/growth/tools-databases/cosing - official EU source
• INCI Decoder: incidecoder.com - clear, easy to find
• Cosmile Europe: cosmile.org - database with safety information

Frequently asked questions

Do I have to specify water (AQUA) in the INCI? Yes. Water remains in the soap in small amounts (usually 5-10%) and must be listed as AQUA in descending order. Without water, the INCI list is not complete.

Can I use the trade name of the oil instead of the INCI? No. The trade name (e.g. "certified organic coconut oil“) is not INCI. You must include the INCI name (Cocos nucifera oil or Sodium cocoate, depending on whether it is saponified) on the label.

If I have less than 1% of an ingredient, in what order do I list it? Ingredients below 1% can be listed in any order AFTER you have listed all ingredients above 1%. So you can have "1% or less: LAVANDULA ANGUSTIFOLIA OIL, CI 77891″.

How do I verify that I haven't forgotten the allergen? Žádejte od dodavatele FO/EO seznam alergenů s jejich koncentracemi. Pak sami spočítejte: alergen v FO (%) × procento FO v mýdle = procento alergenu v hotovém mýdle. Pokud > 0,01 % → musíte uvést.

Are the INCIs for KOH and NaOH soaps different? Yes, slightly. For NaOH, Sodium cocoate is formed, for KOH, Potassium cocoate is formed. They're both correct INCIs, they're just different salts.

What if the oil supplier changes? If you change the supplier of the same oil (e.g. olive from company A to olive from company B), the INCI name remains the same (Olea europaea fruit oil). The label does not change, but the CPSR should at least be reviewed to verify that the new oil has the same toxicological properties.

See also:

• EU regulations for soap makers - complete guide to legislation
• CPSR, PIF, CPNP - documentation for sale
• Cost of legal production - indicative costs of regulatory obligations