12 questions to ask any Korean skincare manufacturer
Reviewed by our formulation chemist team and Minjoon Koo, founder. Updated November 2026.
Ask them before the deposit, in writing. A good partner answers all twelve without hesitation. Here is what the answers should look like.
1. Is my batch filled on a GMP line, and which one?
Small runs should be made on the same ISO 22716 GMP lines as large ones, with batch records. Ask for the line's GMP certificate and a photo of the filling room. If small orders are made somewhere else, the quality is different.
2. Where do the raw materials come from?
Korean labs buy from a known group of ingredient suppliers, many of them the same ones the largest brands use. Ask for the supplier certificate of analysis on the key actives, and whether the manufacturer keeps retained samples of each batch.
3. Who owns the formula?
For custom work, the formula developed for you should not be offered to other brands. For library formulas, your adjusted version, packaging and label should be yours. Get it in the quote or in an NDA.
4. What do samples cost, and how many rounds are included?
Expect library samples within about two weeks in a USD 129 sample box, and a development fee of USD 399 for an adjusted or fully custom formula; both are credited against your first order. Each credit applies when your first production order is placed within 6 months of the sample order or fee payment. Three revision rounds are included, then USD 99 per revision; most brands approve on the second.
5. Which tests are included and which are extra?
Stability and microbiology should come with every product. Challenge tests, safety assessments, SPF and efficacy tests depend on your market and claims. The quote should list each one with a price so nothing appears later.
6. What is the total lead time, and what can delay it?
Samples take about 2 weeks to make and 5 to 10 days by air, then about 4 to 5 weeks of production after you approve them with a library formula, or 4 to 6 weeks with a custom formula. The usual delays are artwork approval, custom packaging and payment timing. Ask how they are tracked.
7. Which documents come with the shipment?
At minimum: certificate of analysis, safety data sheet, full ingredient list, certificate of origin, commercial invoice and packing list with HS codes. A manufacturer that has exported its own products will have these ready; one that has not will learn on your order.
8. Can you support my market's registration?
FDA MoCRA listing for the United States, CPNP and a product information file for the EU, SCPN for the UK, notifications for Canada, Australia, Japan, ASEAN and the Gulf. The answer should name the documents and who acts as responsible person.
9. What is the minimum order for the packaging, not just the formula?
Containers, pumps and cartons have their own minimums and lead times. Stock containers should carry no tooling cost. Custom molds start to make sense above about 10,000 units.
Also ask whether the box is in the unit price, and who makes the artwork. At KoreanOEM, stock containers are in the unit price, boxes are always quoted separately, and you or your designer supply print-ready artwork.
10. Who will I actually talk to?
One manager from brief to delivery, in your language, with a response time in writing. Ask whether that person also talks to the lab, or only relays messages.
11. What are the payment terms and methods?
A deposit at order and the balance before shipment is standard, by bank transfer. Be careful with full prepayment before a pre-production sample is approved.
12. Can I see the lab and the line?
Ask what they can show you: certificates, batch records and retained samples. A maker that shows nothing is giving you an answer too.
Questions for a specific product? See sunscreen, serum or sheet masks.