Ask three laboratories what testing your cosmetic needs and you may get three different quotes. The reason is rarely science — it is that most quotes are built from a standard package rather than from your formulation. Working out which cosmetic tests do you need is not guesswork: it follows almost entirely from one question about your product.
Does it contain water?
That single fact decides whether you need microbiological testing and a preservative efficacy challenge test, or whether those two can be left out entirely. This guide sets out the rule, gives you a product-group table to find yourself in, and explains what stays mandatory no matter what you make.
Key takeaways
- Every cosmetic on the EU market needs a Product Information File and a Cosmetic Product Safety Report. Neither is negotiable.
- Stability and compatibility testing applies to every product, wet or dry.
- Microbiological testing and the challenge test exist to address microbial growth, which requires available water.
- Anhydrous products — oils, powders, waxes, high-alcohol sprays — generally do not need those two tests.
- Products with a water phase need all five, because a preservative system has to be proven, not assumed.
- Aerosols carry extra rules on top and need a dedicated assessment.
The two documents nobody escapes
Before testing enters the conversation, two things are mandatory for every cosmetic placed on the EU market under Regulation (EC) No 1223/2009. The Product Information File is the dossier you must hold and keep accessible to authorities for ten years. The Cosmetic Product Safety Report is the safety assessment inside it, split into Part A (the safety information) and Part B (the assessor’s reasoned conclusion).
Laboratory testing is not an alternative to these. It is the evidence that populates them. If you are unclear on how the documents relate, our explainer on CPSR vs PIF vs SDS untangles them.
Why water is the deciding factor
Bacteria, yeasts and moulds need free water to grow. The technical measure is water activity — roughly, how much unbound water is available to microorganisms. Above about 0.6, microbial growth is possible. Below it, most organisms cannot multiply.
That is why two of the five tests are conditional:
- Microbiological testing establishes the microbiological quality of your finished product — total viable counts and the absence of specified organisms. It tells you what is in the batch you made.
- Preservative efficacy testing, the challenge test, deliberately inoculates your product with organisms and measures whether the preservative system kills them off over time. It tells you what will happen after a consumer opens the jar and puts their fingers in it.
Both are answering a question that a genuinely anhydrous product does not raise. Our older explainers on the role of microbiological testing and preservative efficacy testing go deeper into the methods themselves.
Find your product group
The table below maps common product groups to the tests they require. It uses hair care as the worked example because the category spans the full range — from liquid shampoos to dry powders to alcohol sprays — but the logic transfers to any cosmetic category.
| Product group | PIF | CPSR | Microbiological | Challenge test | Stability |
|---|---|---|---|---|---|
| Shampoo (liquid) | Yes | Yes | Yes | Yes | Yes |
| Conditioner (liquid) | Yes | Yes | Yes | Yes | Yes |
| Hair mask | Yes | Yes | Yes | Yes | Yes |
| Hair serum (water-based) | Yes | Yes | Yes | Yes | Yes |
| Hair oil (without water) | Yes | Yes | — | — | Yes |
| Leave-in conditioner | Yes | Yes | Yes | Yes | Yes |
| Styling gel | Yes | Yes | Yes | Yes | Yes |
| Hair mousse | Yes | Yes | Yes | Yes | Yes |
| Dry shampoo (powder) | Yes | Yes | — | — | Yes |
| Hair spray (alcohol base) | Yes | Yes | — | — | Yes |
| Hair wax / pomade | Yes | Yes | — | — | Yes |
| Hair dye | Yes | Yes | Yes | Yes | Yes |
| Any product with a water phase | Yes | Yes | Yes | Yes | Yes |
| Any product without a water phase | Yes | Yes | — | — | Yes |
| Any product with high alcohol content | Yes | Yes | — | — | Yes |
Stability is not the test you skip
Brands sometimes assume that an anhydrous product, having escaped two microbiological tests, needs no testing at all. That is the one dangerous conclusion to draw from the table.
Oils oxidise and turn rancid. Powders cake, clump and absorb atmospheric moisture. Waxes bloom on the surface. Emulsions separate. And every formulation can interact with its packaging — fragrance components migrating into plastic, actives degrading under light, a closure failing over eighteen months. Accelerated stability and compatibility testing is what establishes your shelf life and your period after opening, and it applies to everything.
What this means for your quote
Once you know your profile, you can tell whether a quote makes sense. A supplier offering one cosmetic testing package regardless of formulation is either overselling anhydrous products or underselling water-based ones.
For a formulation with a water phase, the Water-Based Cosmetic Safety Package covers the full set — PIF, CPSR, microbiological testing, challenge test and stability testing — at a discount against ordering separately, with the CPSR component scaling to your ingredient count.
If your product has no water phase, the Anhydrous & Alcohol-Based Safety Package deliberately leaves the two microbiological tests out, and costs less as a result.
Bringing it all together
Testing requirements are far more predictable than the market makes them look. A PIF, a CPSR and a stability test apply to every cosmetic. Microbiological testing and a challenge test apply when there is water available for organisms to grow in. Aerosols need extra work on top, and genuinely borderline formulations need a human judgement rather than a lookup.
Find your product group in the table, confirm whether water is present, and you already know your quote before you ask for one. If you are unsure which side of the line you fall on, send the formulation over — the honest answer is sometimes the cheaper package.
Frequently asked questions
Which tests are mandatory for every cosmetic in the EU?
A Product Information File and a Cosmetic Product Safety Report are mandatory for every cosmetic product. Stability and compatibility testing applies to every product in practice, because you cannot substantiate a shelf life or a period after opening without it. Microbiological and challenge testing depend on whether your formulation contains water.
Why do anhydrous cosmetics need fewer tests?
Microbiological testing and preservative efficacy testing both address microbial growth, and microorganisms need available water to multiply. A product with no water phase does not present that risk, so those two tests fall away. See our guide to challenge test exemptions for the underlying criteria.
Does a high alcohol content count as anhydrous?
A sufficiently high alcohol content can make a formulation self-preserving even where water is present, which is why alcohol-based sprays sit on the anhydrous side of the table. Because the threshold matters and formulations differ, this is one to confirm against your actual recipe rather than assume.
Do I need a challenge test if I already did microbiological testing?
Yes, for a water-containing product. Microbiological testing tells you the quality of the batch you produced. The challenge test tells you whether your preservative system will withstand contamination introduced by the consumer during use. They answer different questions and neither substitutes for the other.
What about soap?
Solid soap has a high pH and low water activity, which usually places it in the reduced-testing group, though the assessment still has to be made product by product. Our guide to handmade soap safety covers cold-process and melt-and-pour specifics.
My product is in an aerosol can. Does the table still apply?
The tests in the table still apply according to whether water is present, but aerosols carry additional requirements on top and need a dedicated aerosol safety assessment covering pressure, flammability and propellant behaviour. Contact us with the specification rather than ordering a standard package.
How much does the testing cost?
The individual tests are fixed-price and published on each service page. The CPSR scales with the number of ingredients in your formula, so the total depends on formulation complexity. Both product-group packages show the exact figure before you add to cart.
