Thiamine Hydrochloride (Vitamin B1) from Mexico
Thiamine hydrochloride contains a substituted pyrimidine-thiazolium structure with an unfused aromatic thiazole ring, classified as a vitamin but tariffed as its heterocyclic component. Falls under HTS 2934.10.20.00 as 'other' aromatic thiazole compound per Chapter 29 precedence. The thiazole ring determines classification over vitamin function.
Duty Rate — Mexico → United States
110%
Rate breakdown
9903.04.6093.5%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include USP/NF certificate confirming thiazole content despite vitamin labeling
• FDA registration required; declare pharmaceutical grade to avoid food supplement reclassification
• Specify 'thiazole derivative' on commercial invoice to support HTS 2934.10 classification