Product classification
HS code for Phthalic anhydride: 2917.35
Acids, aromatic polycarboxylic acids, phthalic anhydride.
Classification of phthalic anhydride under HS 2917.35
Phthalic anhydride is classified under HS code 291735. This classification is situated within Chapter 29 (Organic Chemicals) and heading 2917, which covers polycarboxylic acids, their anhydrides, halides, peroxides, and peroxyacids. Subheading 291735 is a specific, named entry for phthalic anhydride. The classification is based on the chemical identity of the substance as the anhydride of phthalic acid, an aromatic polycarboxylic acid. It is produced industrially by the catalytic oxidation of orthoxylene or naphthalene. In the global market, it is a critical intermediate used in the manufacture of phthalate plasticizers, alkyd resins, and polyester resins. Because it is a specifically named chemical in the Harmonized System, its classification is straightforward under GRI 1, provided the product is a separate chemically defined compound. It is typically traded as white crystalline flakes or in a molten state in heated tankers, both of which fall under this specific HS code.
- Covers
- Pure phthalic anhydride (99%+)
- Industrial grade phthalic anhydride flakes
- Molten phthalic anhydride
- Phthalic anhydride for resin manufacturing
- Also under 2917.35
- BASF Phthalic Anhydride
- Koppers Phthalic Anhydride
- Polynt Phthalic Anhydride
- IG Petrochemicals PA
- UPC Technology PA
Codes often confused with 2917.35
Common mistake. Phthalic anhydride is sometimes misclassified under 291739, which is the 'other' category for aromatic polycarboxylic acids. It may also be confused with 291732 (Dioctyl orthophthalates) or 291734 (Other esters of orthophthalic acid), which are the finished plasticizers produced from the anhydride rather than the anhydride itself.
Top exporters and importers of HS 291735 (the code used for phthalic anhydride), 2025
In 2025, the largest exporter of HS 291735 (the code used for phthalic anhydride) in UN Comtrade data was China, with 20% of world exports; the largest importer in UN Comtrade data was Türkiye, with 8.4% of world imports. Taiwan did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 19% of its exports here ($21M, CEPII BACI), so it may rank higher.
Figures cover everything classified under HS 291735, not only phthalic anhydride.
Top exporters 2025 · share of world exports
- 1 China $135M 20% of world exports
- 2 Belgium $95M 14% of world exports
- 3 Taiwan* ~$90M 13% of world exports · partner records ↗
Taiwan did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 19% of its exports here ($21M, CEPII BACI), so it may rank higher.
World total: $683M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Türkiye $62M 8.4% of world imports
- 2 Italy $60M 8.3% of world imports
- 3 India $57M 7.8% of world imports
World total: $732M Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries marked * did not, so their figures add up what other countries recorded trading with them, and their exports are valued at buyers' CIF prices. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. UN Comtrade records Taiwan as "Other Asia, not elsewhere specified". Saudi Arabia's exports under that code are left out: they are far too large to be trade with Taiwan, so mostly undisclosed partners. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for phthalic anhydride
Brazil classifies phthalic anhydride under NCM 2917.35.00: HS 2917.35 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about phthalic anhydride
What is the HS code for Phthalic anhydride?
The HS code for Phthalic anhydride is 291735 (Acids; aromatic polycarboxylic acids; phthalic anhydride). The specific HS code for phthalic anhydride is 291735.
How do I classify Phthalic anhydride for customs?
Phthalic anhydride is classified under HS code 291735 — Acids; aromatic polycarboxylic acids; phthalic anhydride. This is a 6-digit subheading level code.
Is phthalic acid classified under the same code?
No, phthalic acid is classified under HS code 291739, as 291735 is specifically reserved for the anhydride form.
Which countries are the top exporters of phthalic anhydride (HS 291735)?
In 2025, the top exporters of HS 291735 (the code used for phthalic anhydride) in UN Comtrade data were China ($135M, 20% of world exports), Belgium ($95M) and Taiwan (about $90M). World exports came to about $683M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Taiwan did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 19% of its exports here ($21M, CEPII BACI), so it may rank higher.
Which countries are the top importers of phthalic anhydride (HS 291735)?
In 2025, the top importers of HS 291735 (the code used for phthalic anhydride) in UN Comtrade data were Türkiye ($62M, 8.4% of world imports), Italy ($60M) and India ($57M). World imports came to about $732M, 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.
Is the HS code for Phthalic anhydride the same in all countries?
The base HS code 291735 for Phthalic anhydride is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for phthalic anhydride in Brazil?
In Brazil, phthalic anhydride (HS 291735) is classified under NCM 2917.35.00.