Product classification
HS code for Hydantoin: 2933.21
Heterocyclic compounds, with nitrogen hetero-atom(s) only, containing an unfused imidazole ring (whether or not hydrogenated) in the structure, hydantoin and its derivatives.
Classification of hydantoin under HS 2933.21
Hydantoin and its derivatives are classified under HS code 2933.21. This code is situated within Chapter 29, which covers organic chemicals. Heading 2933 is dedicated to heterocyclic compounds with nitrogen hetero-atom(s) only. Specifically, the 2933.2x group covers compounds containing an unfused imidazole ring, whether or not hydrogenated. Hydantoin (glycolylurea) is a heterocyclic organic compound with the formula CH2C(O)NHC(O)NH. It is considered a cyclic urea. The classification 2933.21 is a specific named subheading, which takes precedence over more general subheadings like 2933.29 according to GRI 1. The chemical structure must feature the five-membered ring containing two nitrogens at positions 1 and 3. Derivatives of hydantoin, such as those used in the production of anticonvulsants, disinfectants, or resins, remain in this code provided they do not have other functional groups that would move them to a different chapter or heading. For example, if the hydantoin derivative is formulated as a medicament for retail sale, it would be classified in Chapter 30. However, as a pure chemical or a bulk derivative, 2933.21 is the correct designation.
- Covers
- Hydantoin (Glycolylurea)
- 5,5-Dimethylhydantoin (DMH)
- Allantoin (a hydantoin derivative)
- Phenytoin (bulk pharmaceutical grade)
- 1,3-Dibromo-5,5-dimethylhydantoin
- Also under 2933.21
- Dilantin (Phenytoin)
- specific cosmetic preservatives containing DMDM Hydantoin
- generic hydantoin bulk chemicals from chemical suppliers
Codes often confused with 2933.21
Common mistake. Hydantoin is often confused with 2933.29, which is the residual category for other imidazole derivatives. It can also be misclassified under 3004.90 if it is imported as a finished pharmaceutical product (e.g., anti-seizure medication) rather than a raw chemical compound.
Top exporters and importers of HS 293321 (the code used for hydantoin), 2025
In 2025, the largest exporter of HS 293321 (the code used for hydantoin) in UN Comtrade data was China, with 25% of world exports; the largest importer in UN Comtrade data was the United States, with 18% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 293321, not only hydantoin.
Top exporters 2025 · share of world exports
- 1 China $17M 25% of world exports
- 2 Taiwan* ~$9.5M 14% of world exports · partner records ↗
- 3 United States $8.3M 12% of world exports
World total: $70M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $16M 18% of world imports
- 2 Japan $7.6M 8.5% of world imports
- 3 Germany $7.1M 7.9% of world imports
World total: $90M 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 codes for hydantoin
Brazil splits HS 2933.21 into 4 NCM codes. Pick the one that matches your product:
- 2933.21.10Iprodione
- 2933.21.21Phenytoin and its sodium salt
- 2933.21.29Other phenytoin salts
- 2933.21.90Other hydantoin and its derivatives
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about hydantoin
What is the HS code for Hydantoin?
The HS code for Hydantoin is 293321 (Heterocyclic compounds; with nitrogen hetero-atom(s) only, containing an unfused imidazole ring (whether or not hydrogenated) in the structure, hydantoin and its derivatives). The HS code for hydantoin and its derivatives is 2933.21.
How do I classify Hydantoin for customs?
Hydantoin is classified under HS code 293321 — Heterocyclic compounds; with nitrogen hetero-atom(s) only, containing an unfused imidazole ring (whether or not hydrogenated) in the structure, hydantoin and its derivatives. This is a 6-digit subheading level code.
Are all imidazole derivatives under this code?
No, only hydantoin and its specific derivatives are under 2933.21. Other unfused imidazole derivatives are classified under 2933.29.
Which countries are the top exporters of hydantoin (HS 293321)?
In 2025, the top exporters of HS 293321 (the code used for hydantoin) in UN Comtrade data were China ($17M, 25% of world exports), Taiwan (about $9.5M) and the United States ($8.3M). World exports came to about $70M, 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.
Which countries are the top importers of hydantoin (HS 293321)?
In 2025, the top importers of HS 293321 (the code used for hydantoin) in UN Comtrade data were the United States ($16M, 18% of world imports), Japan ($7.6M) and Germany ($7.1M). World imports came to about $90M, 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 Hydantoin the same in all countries?
The base HS code 293321 for Hydantoin 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 hydantoin in Brazil?
Brazil splits HS 293321 into 4 NCM codes, so the right one for hydantoin depends on the product's details: 2933.21.10 (Iprodione), 2933.21.21 (Phenytoin and its sodium salt), 2933.21.29 (Other phenytoin salts), 2933.21.90 (Other hydantoin and its derivatives).