You have a finished formula and are ready to book testing. The next practical question is how many bottles, jars or pots to send — and whether your normal retail size is enough.
The short answer is: send one sample per testing stage purchased, plus one extra for the initial test. Each sample should be a full retail-size product, or at least 50 g / 50 mL. Confirm how that rule applies to your testing programme before posting, especially for small packs or combined testing.
This guide explains the quantity rule, what to prepare for each product and how to avoid sending a parcel that needs more information or additional samples.
How many packaged samples should you send?
Our submission rule is one sample per testing stage purchased, plus one extra for the initial test. The initial sample allows the product to be assessed before the later testing stages.
For an order with one testing stage, that means two packaged samples of each product. With two stages, it means three samples; with three stages, it means four. These are examples of the counting rule, not a recommendation to choose a particular number of stages.
Do not use the number of months, products or payment instalments as a substitute for the number of testing stages. If you are unsure how many stages apply to your order, ask us to confirm the required quantity before packing.
Your programme depends on the work you book. Review the accelerated stability testing service and, where relevant, preservative efficacy testing, then confirm the sample allocation for your order rather than assuming the same parcel covers every test.
What size should each sample be?
Our current guidance is a full retail-size product, or at least 50 g / 50 mL of each sample, so there is enough material for the testing work. Grams describe mass and millilitres describe volume; they are not interchangeable for every formula.
If your product is sold in a 30 mL bottle, tell us that before posting. Confirm whether the planned number of full retail bottles provides enough material or whether additional product is needed. A larger total quantity spread across several bottles is not automatically the same as the required allocation for each stage.
For a 50 g pot, specify both the filled quantity and the number of pots you intend to send. Do not assume a small pot, a partly used unit or a container's nominal capacity is sufficient without checking.
Use the intended retail packaging
Where the testing includes assessment in the intended pack, send the product in the packaging you plan to sell: the relevant bottle, jar, tube, pump or closure. The formula and its container need to be considered together.
A sample transferred from a retail bottle into a different jar does not represent the same packaging combination. Do not combine several small retail units into a bulk container unless the laboratory has agreed that arrangement.
If one formula will be sold in different packaging formats, tell us before booking. We can confirm the scope and sample requirements rather than treating one tested pack as evidence for every alternative.
Prepare a separate sample set for each formula
Each product being tested needs its own clearly identified sample set. Two facial oils with different formulas, for example, should not be grouped as one product simply because both are oils.
Use a consistent product name on the containers and submission form. Include your business or brand, a batch reference and manufacturing date where available, and the amount supplied. Keep your own record of what you sent.
Tell us if the formula or packaging has changed since you obtained your quote. Testing should assess the version you intend to sell, not an earlier prototype that no longer represents the finished product.
What about anhydrous oils, balms and butters?
Tell us when a product is anhydrous, meaning it does not contain a water phase, and describe its intended physical form. Oils, balms and butters can need a different testing approach from water-based emulsions.
A balm designed to soften or melt during use should be identified as such before the programme is agreed. Its intended behaviour matters when discussing test conditions and interpreting changes.
Do not assume anhydrous means that no testing is needed, or that a generic sample count applies to every oil or balm. Confirm the programme and quantities for the actual formula and packaging.
Complete the ingredient information and paperwork
Prepare the full ingredient list and the concentration information requested in the submission form, along with the product description, quantity supplied and relevant batch details. Include any special instructions that could affect handling or assessment.
Clients ordering through an invited retail account can save their brands, products and ingredients and complete the required brand paperwork before checkout. If you order through the public quote tool, use the secure order portal supplied after payment to complete the required information.
In either flow, complete the required paperwork before posting. Avoid relying on a loose note in the parcel as the only record of the formula or the testing request.
Allow for preparation and delivery as well as laboratory work. Our guide to how long cosmetic stability testing takes explains the testing timeline; a launch date should also allow time to resolve missing information or make changes if needed.
Your checklist before posting samples
Confirm the number of testing stages and the required packaged samples for each product. Check the sample size, the allocation for any combined tests and whether the intended retail packaging is required.
Make sure every container can be matched to its submission form. Complete the ingredient information and required agreements, use the current postal instructions in your order portal, and protect containers against leakage or damage in transit.
If you are sending from outside Australia, ask us to confirm the arrangements before dispatch and check the carrier's requirements for the contents. Do not assume all products, ingredients or shipping routes have the same rules.
Ready to start? Get an instant testing quote. If your pack size or sample allocation is unclear, contact the laboratory with the product type, pack size, number of formulas and testing you need before sending your parcel.
Frequently Asked Questions
How many samples do I send for cosmetic stability testing?
Send one sample per testing stage purchased, plus one extra for the initial test. For example, one stage requires two packaged samples of each product; two stages require three. Confirm the number of stages and sample allocation for your order before posting.
Can I send 30 mL retail bottles?
Our guidance allows full retail-size products, or samples of at least 50 g / 50 mL. For a 30 mL retail bottle, confirm the required bottle count and whether additional product is needed before posting. Do not change the packaging or combine bottles without agreement.
Do different formulas need separate sample sets?
Yes. Each product being assessed needs its own identified samples and submission information. Tell the laboratory about formula or packaging differences so the scope and quantities can be confirmed.
Do I need to provide the ingredient list as well as finished samples?
Prepare the full ingredient list and any concentration information requested in your submission form, together with product and batch details. Complete the required paperwork before sending the finished samples.
Can I use a different container for testing?
Where the programme assesses the product in its intended retail packaging, a different container does not represent the same packaging combination. Confirm any alternative sample format with the laboratory before sending it.