HS Code 29.18 – Acids; carboxylic acid with additional oxygen function and their anhydrides, halides, peroxides, peroxyacids; their halogenated, sulphonated, nitrated or nitrosated derivatives

HS code 2918 is a 4-digit heading in the Harmonized System that covers: Acids; carboxylic acid with additional oxygen function and their anhydrides, halides, peroxides, peroxyacids; their halogenated, sulphonated, nitrated or nitrosated derivatives. Heading 2918 covers carboxylic acids with additional oxygen functions, along with their anhydrides, halides, peroxides, peroxyacids, and their halogenated, sulphonated, nitrated, or nitrosated derivatives. This category is for compounds that possess a carboxyl group (-COOH) and at least one other oxygen-containing functional group, such as a hydroxyl (-OH), ether (-O-), aldehyde (-CHO), or ketone (>C=O) group. Examples include lactic acid (with a hydroxyl group) and salicylic acid (with both a hydroxyl and a carboxylic group on an aromatic ring). This heading is distinct from 2916 (monocarboxylic acids) and 2917 (polycarboxylic acids) in that the 'additional oxygen function' is the defining characteristic when the product does not primarily fit the descriptions of 2916 or 2917. These compounds are crucial in pharmaceuticals (e.g., aspirin), cosmetics, food preservation, and various industrial applications. Accurate classification is paramount for regulatory compliance, especially given the diverse end-uses and potential for both therapeutic and industrial applications. It falls under Chapter 29, signifying its importance as a specific organic chemical class.

Lactic acid, salicylic acid, gluconic acid, malic acid, tartronic acid, glycolic acid, ricinoleic acid, mandelic acid, gallic acid, vanillic acid, methyl salicylate, acetylsalicylic acid (aspirin), sodium lactate, calcium gluconate, ethyl pyruvate, pyruvic acid, ascorbic acid (Vitamin C), dehydroacetic acid, para-hydroxybenzoic acid, protocatechuic acid, dihydroxybenzoic acid, alpha-hydroxy acids (AHAs), beta-hydroxy acids (BHAs)

Misclassification under HS 2918 often stems from overlooking the 'additional oxygen function' criterion. Traders might confuse these products with HS 2916 (monocarboxylic acids) or HS 2917 (polycarboxylic acids) if the other oxygen groups are not given due consideration. For instance, citric acid, though having a hydroxyl group, is primarily a tricarboxylic acid and thus falls under 2917, not 2918. Another common mistake is classifying complex esters or salts of these acids under more general ester headings if their direct relationship to the acid with an additional oxygen function isn't clearly established. Aspirin (acetylsalicylic acid) is a classic example that often requires careful consideration to correctly place it here due to its specific chemical structure.

In 2025, the top exporters of HS code 2918 in UN Comtrade data were China ($3.3B, 38% of world exports), India ($692M) and Germany ($674M). World exports came to about $8.7B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

In 2025, the top importers of HS code 2918 in UN Comtrade data were the United States ($1.5B, 15% of world imports), Germany ($827M) and India ($543M). World imports came to about $10.2B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

HS code 2918 is a 4-digit heading under Chapter 29 of the Harmonized System. The first 2 digits (29) identify the chapter, and digits 3-4 (18) specify the heading. This code contains multiple 6-digit subheadings for precise product classification.