</>Build with Tariff Intelligence|Programmatic access to tariff calculations and HS code classification.Explore Developer Resources →

3-Mercaptopropanoic Acid from China

3-Mercaptopropanoic acid features a three-carbon chain with terminal mercapto and carboxylic acid groups. This separate chemically defined compound qualifies under HTS 2930.90.4920 as a mercaptocarboxylic acid per Chapter 29 scope. Applied in polymer cross-linking and biochemical research.

Duty Rate — China → United States

125%

Rate breakdown

9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.04.6095.8%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)

Import Tips

Certify CAS 107-96-0 and molecular formula C3H6O2S for accurate 2930.90.4920 heading

Package with stabilizer if required; document per Chapter 29 note 2(f) to maintain pure compound status

Prevent reclassification to 3824 by limiting solvent to <10% for transport safety