U.S. exports of Butene (Butylene) and Its Isomers (HS 290123) totaled $18.2M in August 2026.
Butene (Butylene) and Its Isomers imports of $96K in August 2026 ran 15% above the year-to-date monthly average of $83K.
Last updated: August 2026 dataButene and its structural isomers — including 1-butene, 2-butene, and isobutylene — are C4 unsaturated acyclic hydrocarbons classified under a single 10-digit line (2901230000) as unsaturated. These olefins are critical feedstocks for polyethylene, polypropylene, and synthetic rubber production, as well as fuel-blending components. Canada is the dominant US supplier, with China, France, and South Korea also contributing meaningfully to import volumes. Importers should be aware that Chinese-origin shipments may be subject to Section 301 tariffs.
AI-written summary of the official U.S. Census Bureau trade figures on this page — verify before relying on it.
1 import shipments a month
All butene isomers — 1-butene, cis- and trans-2-butene, and isobutylene — fall under the single 10-digit tariff line 2901230000 as unsaturated acyclic hydrocarbons. There is no separate HTS subdivision by isomer type at the 10-digit level, so the specific isomer should be documented in commercial invoices and technical data sheets for customs purposes.
Yes. Butene originating from China may be subject to Section 301 tariffs in addition to the standard column 1 duty rate. Importers should verify the current Section 301 list status and any applicable exclusions with a licensed customs broker before shipment.
Subheading 4 of 6 in heading 2901
Subheading 290123 · $18.2M of $992.4M
ImportsExports
Imports
$96KYoY · free account
Exports
$18.2MYoY · free account
Low of 7 reported months · imports
Low · free accountOver the twelve months to August 2026, the U.S. imported $778K of Butene (Butylene) and Its Isomers and exported $188.2M.
Through August 2026 · imports 7 of 12 months reported. Source: U.S. Census Bureau.
Trade Directory
List your company under HS 290123 — Butene (Butylene) and Its Isomers, so the companies trading it can find you. Be the first supplier listed.
HS10 import codes under this HS6 parent, each with its own page. Source: U.S. Harmonized Tariff Schedule.
| Code | Description | Imports for consumption | Average duty rate | Dutiable Share |
|---|---|---|---|---|
| 2901230000 | Butene (Butylene) and Isomers Thereof | $96K | 0.00% | 0.00% |
HS10 export codes under this HS6 parent, each with its own page. Source: U.S. Schedule B export classification.
| Code | Description | Export Value |
|---|---|---|
| 2901230000 | Butene (Butylene) and Isomers Thereof, Unsaturated | $18.2M |
Import lines come from the U.S. Harmonized Tariff Schedule and export lines from Schedule B. The two are numbered by different agencies, so the same 10-digit code can appear in both tables describing a different product.
Exports · August 2026
destination
Canada and Brazil together take 100% of it.
customs district
origin
entry
rate provision · imports
100.0% enters free of duty; duty collected equals 0.00% of imports for consumption.