HS Code 400231
Isobuteneisoprene
Official description: Synthetic rubber and factice derived from oils, in primary forms or in plates, sheets or strip; mixtures of any product of heading 4001 with any product of this heading, in primary forms or in plates, sheets or strip : Isobuteneisoprene (butyl) rubber (IIR); haloisobuteneisoprene rubber (CIIR or BIIR) : Isobuteneisoprene (butyl) rubber (IIR)
Also searched as: butyl rubber, IIR, isobutylene-isoprene rubber, butyl bale
Classification
How 400231 breaks down
Rubber and articles thereof
Synthetic rubber and factice derived from oils, in primary forms or in plates, sheets or strip; mixtures of any product of heading 4001 with any product of this heading, in primary forms or in plates, sheets or strip
Isobuteneisoprene (butyl) rubber (IIR)
Covered products
What products fall under HS code 400231?
Buyers sourcing isobuteneisoprene from 1688 commonly describe it in these ways. If your product matches, 400231 is likely the right 6-digit starting point — confirm material and intended use against the official tariff.
Import duty by market
Where to check the import duty for HS 400231
The 6-digit code is universal, but duty, VAT and GST are set by the destination country and depend on the full national tariff line with China as the country of origin. Start from the official source for your market.
United States
USITC / CBP · Harmonized Tariff Schedule (HTS)
European Union
TARIC · Access2Markets
United Kingdom
HMRC · UK Integrated Online Tariff
Canada
CBSA · Canadian Customs Tariff
Australia
ABF · Australian customs tariff
Singapore
Singapore Customs · Singapore Trade Classification (HS)
Compare the real China-origin import tax across markets
Use the HS & import duty checker to estimate duty + VAT/GST for 400231 by destination before you pay a 1688 supplier.
Heading 4002
Other HS codes under 4002
Subheadings in the same 4-digit heading — "Synthetic rubber and factice derived from oils, in primary forms or in plates, sheets or strip; mixtures of any product of heading 4001 with any product of this heading, in primary forms or in plates, sheets or strip". If 400231 is not an exact match, one of these may classify your product more precisely.
Questions
HS code 400231: common questions
What is HS code 400231?
HS code 400231 is the World Customs Organization 6-digit HS 2022 subheading for "Synthetic rubber and factice derived from oils, in primary forms or in plates, sheets or strip; mixtures of any product of heading 4001 with any product of this heading, in primary forms or in plates, sheets or strip : Isobuteneisoprene (butyl) rubber (IIR); haloisobuteneisoprene rubber (CIIR or BIIR) : Isobuteneisoprene (butyl) rubber (IIR)". The first two digits (40) are the chapter — Rubber and articles thereof — and digits 3-4 (4002) are the heading. Countries add further digits (8-10) for their national tariff line.
What products fall under HS 400231?
Common products classified under 400231 include butyl rubber, IIR, isobutylene-isoprene rubber, butyl bale and similar items matching isobuteneisoprene. The correct code still depends on the product's material, function and intended use.
How do I find the import duty for HS code 400231?
Duty is set by the destination country, not by the 6-digit HS code alone. Start from the official tariff of your market — USITC HTS (US), TARIC / Access2Markets (EU), GOV.UK Trade Tariff (UK), CBSA (Canada), ABF (Australia) or Singapore Customs — and look up the full national code with China as the country of origin.
Is HS code 400231 the same in every country?
The first 6 digits (400231) are the same worldwide under the WCO Harmonized System. Beyond that, each country extends the code (HTS in the US, TARIC in the EU, etc.) and sets its own duty and tax rates.
Can I trust the HS code a 1688 supplier gives me?
Treat a supplier-provided code as a clue, not a final classification. It can be incomplete, China-export-specific, or mismatched to your destination's rules. Verify against the official tariff and your product's actual material and use.
Chapter 40
Explore Rubber and articles thereof
Sourcing isobuteneisoprene from 1688?
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