HS code · 6-digit subheading
HS Code 3903.11 – Styrene polymers; expansible polystyrene, in primary forms
HS code 3903.11 is the 6-digit subheading for styrene polymers, expansible polystyrene, in primary forms. It is used for EPS beads, pre-expanded EPS beads, flame-retardant EPS, high-density EPS and low-density EPS.
What HS 3903.11 covers
This HS code specifically covers expansible polystyrene (EPS) in its raw, primary forms, typically as beads containing a blowing agent like pentane. It's a critical material for insulation and protective packaging due to its ability to expand significantly when heated, forming lightweight, shock-absorbing, and thermally insulating foam. Chemical manufacturers are the primary exporters, while construction companies, packaging manufacturers, and appliance makers are the main importers. Key considerations include the blowing agent's environmental impact and the shift towards more eco-friendly alternatives, fire retardancy requirements for building applications, and the increasing global demand for energy-efficient building materials and protective packaging solutions.
- Covers
- EPS beads
- Pre-expanded EPS beads
- Flame-retardant EPS
- High-density EPS
- Low-density EPS
- Graphite-enhanced EPS
- Recycled content EPS beads
- Examples
- BASF Styropor
- Versalis Edistir
- Sunpor EPS
- TotalEnergies Styrenics EPS
- Synthos EPS
Codes often confused with 3903.11
Common mistake. Can be confused with 390319 (other non-expansible polystyrene) if the 'expansible' characteristic is overlooked, or even 3923 for finished packaging products made from EPS.
Top exporters and importers of HS code 390311, 2025
In 2025, the largest exporter of HS code 390311 in UN Comtrade data was China, with 21% of world exports; the largest importer in UN Comtrade data was Poland, with 12% 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 22% of its exports here ($86M, CEPII BACI), so it may rank higher.
Top exporters 2025 · share of world exports
- 1 China $501M 21% of world exports
- 2 Netherlands $291M 12% of world exports
- 3 Taiwan* ~$213M 9.1% 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 22% of its exports here ($86M, CEPII BACI), so it may rank higher.
World total: $2.3B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Poland $468M 12% of world imports
- 2 United States $384M 10% of world imports
- 3 Italy $196M 5.2% of world imports
World total: $3.8B 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 3903.11 2
Brazil splits HS 3903.11 into 2 NCM codes, Mercosur's 8-digit tariff lines.
- 3903.11.10 Expansible polystyrene (EPS) with fillerCom carga
- 3903.11.20 Expansible polystyrene (EPS) without fillerSem carga
All Brazil NCM codes in heading 39.03 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 3903.11
What is HS code 390311?
HS code 390311 is a 6-digit subheading in the Harmonized System that covers: Styrene polymers; expansible polystyrene, in primary forms. This HS code specifically covers expansible polystyrene (EPS) in its raw, primary forms, typically as beads containing a blowing agent like pentane. It's a critical material for insulation and protective packaging due to its ability to expand significantly when heated, forming lightweight, shock-absorbing, and thermally insulating foam. Chemical manufacturers are the primary exporters, while construction companies, packaging manufacturers, and appliance makers are the main importers. Key considerations include the blowing agent's environmental impact and the shift towards more eco-friendly alternatives, fire retardancy requirements for building applications, and the increasing global demand for energy-efficient building materials and protective packaging solutions.
What products fall under HS code 390311?
EPS beads, pre-expanded EPS beads, flame-retardant EPS, high-density EPS, low-density EPS, graphite-enhanced EPS, recycled content EPS beads
What are common misclassifications for HS code 390311?
Can be confused with 390319 (other non-expansible polystyrene) if the 'expansible' characteristic is overlooked, or even 3923 for finished packaging products made from EPS.
Which countries are the top exporters of goods under HS code 390311?
In 2025, the top exporters of HS code 390311 in UN Comtrade data were China ($501M, 21% of world exports), the Netherlands ($291M) and Taiwan (about $213M). World exports came to about $2.3B, 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 22% of its exports here ($86M, CEPII BACI), so it may rank higher.
Which countries are the top importers of goods under HS code 390311?
In 2025, the top importers of HS code 390311 in UN Comtrade data were Poland ($468M, 12% of world imports), the United States ($384M) and Italy ($196M). World imports came to about $3.8B, 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.
How is HS code 390311 structured?
HS code 390311 is a 6-digit subheading under the Harmonized System. The first 2 digits (39) identify the chapter, digits 3-4 (03) identify the heading, and digits 5-6 (11) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 390311?
Brazil splits HS code 390311 into 2 NCM codes: 3903.11.10 (Expansible polystyrene (EPS) with filler), 3903.11.20 (Expansible polystyrene (EPS) without filler). The first 6 digits of each match the HS code.