Is Your K-Beauty Formula Legal in Korea? An Indie Founder's 2026 MFDS Ingredient Guide

By Liz Song, K-beauty sourcing consultant

Most indie founders assume that if a formula ships from a Korean ODM, it is automatically legal in Korea. It usually is. But the exceptions matter, and they hit new founders hardest during pre-production sample review, when a swap request from the lab lands in your inbox and you have 48 hours to decide whether to accept it, argue it, or lose your holiday launch window.

Korea regulates cosmetic ingredients through the Ministry of Food and Drug Safety, or MFDS. The system looks like the EU CosIng framework at first glance, but the lists are different, the concentration caps are different, and the boundary between a "cosmetic" and a "quasi-drug" is sharper than most US-based founders expect. This is the short reference you can keep open when a chemist emails you at 6 a.m. Seoul time.

What Makes an Ingredient "Restricted" Under Korean Cosmetic Law?

An ingredient is restricted in Korea when the MFDS Cosmetic Standard (Notification 2024-XX and its annexes) either prohibits it outright, caps its concentration, restricts it to specific product categories, or reclassifies it as a quasi-drug active. Anything not on a positive list for preservatives, UV filters, colorants, or hair dyes is presumed not permitted.

Korea's system is a closed positive list for those four categories, and an open negative list for everything else. That is the opposite of how many US founders learn to think about the FDA framework, where cosmetics are effectively self-regulated unless they cross into drug claims. The practical consequence: a US-legal formula built around a novel botanical extract or a niche preservative can fail Korean review even when the raw material has been used elsewhere for years.

The Cosmetics Act (2011, amended repeatedly through 2025) is the statute. The Cosmetic Standard is the notification that operationalizes it. The annexes are where the lists live. When your Korean ODM says "we cannot use that," they are usually pointing at an annex, not making a preference call.

The Four MFDS Ingredient Lists Every Founder Needs to Know

Four lists govern almost every ingredient decision a Korean ODM chemist makes on your formula. Founders who can name them by number have shorter, cleaner review cycles.

Annex 1 (Prohibited Ingredients): ingredients that cannot appear in any cosmetic sold in Korea at any concentration. Roughly 1,000+ entries, including many pharmaceutical actives, certain heavy metals, and specific botanical derivatives.

Annex 2 (Restricted Ingredients): ingredients permitted only under conditions listed in the annex. Conditions are usually maximum concentration, product category restrictions (rinse-off vs. leave-on), and mandatory warning statements. Salicylic acid, for example, sits here with a leave-on skincare concentration cap in the low fractions of one percent (see MFDS Cosmetic Standard, mfds.go.kr).

Annexes 3-5 (Positive Lists): permitted preservatives (Annex 3), permitted UV filters (Annex 4), and permitted colorants (Annex 5). If a preservative, UV filter, or colorant is not on the relevant annex, it cannot be used, full stop. This is where formulations legal in the EU but not in Korea trip up most often.

Quasi-Drug Actives: a parallel list of ingredients approved for whitening, anti-wrinkle, sun protection, or hair loss claims. These sit outside the cosmetic annexes because a product using them is legally a quasi-drug in Korea, not a cosmetic. See the section below.

Which Ingredients Are Outright Banned in Korean Cosmetics?

Annex 1 bans over 1,000 ingredients outright, with concentrations of hydroquinone, tretinoin and other prescription retinoids, certain parabens (isopropyl, isobutyl, phenyl, benzyl, pentyl), triclosan, and several long-standing US-permitted preservatives all on the list. Any formula containing an Annex 1 substance cannot legally be manufactured or sold in Korea.

The list is longer than the FDA's cosmetic ingredient prohibitions and updates roughly annually. High-profile removals in recent years include certain siloxanes (D4, D5 in wash-off products above threshold) and specific microplastic particles. High-profile additions have included several endocrine-disrupting UV filters that Europe has restricted.

A brand-new founder's most common Annex 1 trap: assuming a peptide or growth factor cleared for cosmetic use elsewhere is fine in Korea. EGF (epidermal growth factor) is a quasi-drug active in Korea, not a cosmetic ingredient. Copper tripeptide is permitted as a cosmetic ingredient. The difference is not obvious from the INCI name.

Your ODM will filter Annex 1 substances automatically on any new brief. The risk is when a founder pushes for an ingredient after seeing it in a US or Japanese launch. Ask, do not assume.

Restricted Ingredients: When Concentration Caps Change Your Formula

Annex 2 restricts hundreds of ingredients to specific concentration caps or product categories, and this is where most founder-versus-lab friction happens. The ingredient is legal. The concentration you specified may not be.

A partial working list founders hit constantly. All caps in the table below are drawn from the MFDS Cosmetic Standard, published at https://www.mfds.go.kr/eng/index.do.

The pattern is simple. When an ingredient does something clinically meaningful (fades pigment, smooths lines, protects from UV), Korea often drops it into the quasi-drug regime rather than allowing an unbounded cosmetic use. Your ODM will hold that line even when a US brand you admire is running higher salicylic in a leave-on. That brand is not selling in Korea, or is not selling that formula in Korea.

What Are "Quasi-Drug" Actives and Why Do They Trigger Special Approval?

A quasi-drug is Korea's third product class, sitting between a cosmetic and a pharmaceutical drug. Any product making a whitening, anti-wrinkle, sun protection, hair loss, acne treatment, or antiperspirant claim, or using an ingredient reserved for those claims, must be filed as a quasi-drug with MFDS. Approval adds 3-6 months and costs more than a standard cosmetic notification.

The reserved actives include, among others: niacinamide at whitening-tier concentrations, alpha-arbutin for whitening, retinol at anti-wrinkle threshold and above, adenosine for anti-wrinkle, and the full MFDS-approved UV filter list for sun protection. Full annex published at https://www.mfds.go.kr/eng/index.do. Use any of these at their reserved concentration or make the reserved claim, and the product is no longer a cosmetic.

Founders shipping to the US often want to say "brightening" or "anti-aging" for marketing reasons, and they want a Korean ODM to make the formula. This works, but the label sold in Korea must not carry the whitening or anti-wrinkle claim unless the product is filed as a quasi-drug. The same formula can carry different claims in different jurisdictions, but the Korean-market SKU must match the Korean-market filing. For a deeper walkthrough of the MFDS vs FDA vs EU claim boundaries, see KFDA vs FDA vs EU cosmetic safety standards.

How to Verify a New Ingredient Against MFDS Before You Sign a PO

Verify every unusual ingredient against MFDS annexes in three steps before signing a purchase order, and always run this check before, not after, sample approval.

Step 1: Confirm the exact INCI name and CAS number. "Bakuchiol" alone is not enough. The specific extract source and any solvent carrier matter for annex lookup. Ask your ODM for the raw material Certificate of Analysis (CoA), which will show the INCI and CAS.

Step 2: Ask for the MFDS compliance statement, not just the CoA. A CoA proves what is in the drum. It does not prove the ingredient is legal at your target concentration in your product category. A one-line MFDS compliance statement from the ODM's regulatory team is what you want. Reputable ODMs (Cosmax, Kolmar, Kolong, Coreana, and mid-tier houses) issue these routinely.

Step 3: Cross-check against the MFDS English portal. The MFDS English site publishes the Cosmetic Standard and quasi-drug regulations. When the ODM's statement and the published annex disagree, escalate. Ambiguity almost always resolves against the founder if a market surveillance action comes later.

If you are still assembling the broader launch stack alongside ingredient verification, our complete guide to starting a K-beauty skincare brand puts this step in sequence with sample review, packaging, and MFDS/FDA notification.

What Happens if a Restricted Ingredient Slips Through?

If MFDS market surveillance flags a restricted ingredient in a finished product, the standard sequence is: recall notice, corrective distribution report within 15 days, administrative fine, and potential suspension of the responsible seller's registration. Repeat violations can trigger criminal referral. For a US indie founder using a Korean ODM, the responsible seller is usually the ODM if the product is sold in Korea, and the brand if the product is sold abroad but was manufactured by a licensed Korean facility.

Practical downstream effects for the brand are larger than the fine. Amazon Korea, Olive Young, and department store buyers all check MFDS compliance history when onboarding. A single recall record makes retail conversations harder for 12-24 months.

For US-only launches, the failure mode is different but still real. If your product is manufactured in Korea and shipped to the US, US Customs and the FDA under MOCRA will accept the Korean facility registration as evidence of GMP compliance. When your Korean facility loses its registration over an ingredient violation, your MOCRA facility listing goes stale, and your next US shipment can be held. Read our FDA Korean skincare import guide for how facility registration flows from MFDS to US customs.

Frequently Asked Questions

Can I include an ingredient that is legal in the EU but not on any MFDS annex?
No, if the ingredient is a preservative, UV filter, colorant, or hair dye. Those four categories are closed positive lists in Korea. For other ingredient types (actives, humectants, extracts), the ingredient is permitted unless it appears on Annex 1 or is captured by a quasi-drug reservation. Verify with an MFDS compliance statement.

How often does the MFDS ingredient list change?
The Cosmetic Standard is amended roughly once or twice a year. Larger overhauls happen every 3-5 years. Set a calendar reminder to re-verify any formula still in production against the current annex before each new production run.

Does my Korean ODM check the MFDS annexes automatically?
Yes for standard formulations built from ODM's own preapproved base. No, or partially, for founder-supplied ingredients or novel actives. Always request written MFDS compliance confirmation for anything you added to the brief.

What is the difference between a cosmetic and a quasi-drug for a niacinamide serum?
A niacinamide serum at a moderate concentration marketed as "hydrating" is a cosmetic in Korea. The same serum at the MFDS whitening-tier concentration (published at https://www.mfds.go.kr/eng) marketed as "whitening" is a quasi-drug and needs separate MFDS approval, additional efficacy testing, and specific label statements. The chemistry is identical; the regulatory class follows the claim.

Can I sell in the US only and skip MFDS checks entirely?
Only if your product is not manufactured in Korea. If any manufacturing step happens in a Korean licensed facility, that facility must maintain its MFDS registration, which in turn requires all formulas produced there to comply with Korean ingredient rules regardless of destination market.

Reviewed for accuracy by ALTA MEET's formulation consulting team.