TIAM

TIAM is a South Korean skincare brand built around vitamin-based formulas, headquartered in Seongnam, in the Gyeonggi province south of Seoul [3]. Its name comes from a Persian word that the company describes as "a twinkle in the eye when you meet someone for the first time" [2]. The brand sits within the broader K-beauty movement, positioning itself around active ingredients such as niacinamide and vitamin C rather than a single hero category.

TIAM remains active. Its direct-to-consumer site carried operational notices into 2026, and the brand ships to more than 30 countries through a network of regional resellers.

No source states a founding year for TIAM, and the founders are not named. The earliest firm signal comes from 2017, when a K-beauty reviewer encountered TIAM representatives at the K-Beauty Expo in Seoul in May of that year and noted that the brand had launched or rebranded only months earlier [5]. That timing points to a launch around late 2016 or early 2017, though no source confirms an exact date.

The brand grew directly out of an existing product. TIAM rebranded the O.S.T Original Pure Vitamin C20 serum — a vitamin C serum with a following in online skincare communities — into what became its own signature line, first as My Signature C Source and later as Vita C Source.

The legal entity behind TIAM is listed on the brand's own contact page as "Fireworks (Tiam)" [3]. A widely repeated claim, originating in a 2017 review and circulated across K-beauty coverage, describes TIAM as a "little sister company of Cosrx" [5]. TIAM's own about and contact pages make no such claim, and the registered company name points to Fireworks rather than a COSRX-related entity. On the available evidence the parent company is Fireworks; the COSRX connection is not corroborated by any brand source.

The brand is written two ways across the market. Its primary site, tiamglobal.com, uses "TIAM" without an apostrophe through the homepage title and most of its copy [1]. Several retailers — including StyleKorean and other resellers — render it "TIA'M" with an apostrophe [6]. TIAM's own footer also carries the apostrophe form once. Following the brand's dominant self-styling, this article treats "TIAM" as the primary name and "TIA'M" as a retailer variant.

TIAM presents itself as a vitamin-focused skincare brand, summed up in the line "Active Skincare. Absolute Answer" [1]. Its stated mission is to understand and address each person's individual skin concerns with tailored solutions [2]. The company frames its approach around three pillars: comprehensive vitamin care, scientific research and innovation, and natural raw materials and safety. On sustainability, TIAM's stated commitment is limited to using safe raw materials and excluding ingredients it considers harmful.

TIAM's range centres on serums, creams and other treatments organised by skin concern, such as acne, dullness and dryness. Its best-known product is the vitamin C serum now sold as Vita C Source, the descendant of the O.S.T C20 formula, which the brand describes as an antioxidant-rich formula built on 20% pure vitamin C [5]. This serum has held a following in online skincare communities, where it circulated under its earlier O.S.T name [5]. Other featured products include the Glow 333 Capsule Cream, the PDRN Collagen Glow Up Serum, the Blue Peptide Calm Down Serum and Vita B3 Source. Across the line, the brand highlights ingredients including niacinamide, vitamin C, hyaluronic acid, snail filtrate and azulene.

TIAM sells directly through tiamglobal.com and through a wide set of specialist K-beauty retailers rather than prestige department stores [4]. Named global partners include Style Korean, YesStyle, Jolse, Stylevana and iHerb, alongside regional resellers across the Americas, Asia, the Middle East, Europe, Africa and Oceania [4].

TIAM is an active brand with global reach. Its direct-to-consumer site was operating with 2026 notices, including shipping updates tied to Korean holidays, and its documented reseller network spans more than 30 countries [4].