Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 3903.90.10.00 is the U.S. Harmonized Tariff Schedule classification for Polymers of styrene, in primary forms, methyl methacrylate-butadiene-styrene (MBS) copolymers. It's a 10-digit statistical line in Chapter 39: Plastics and articles thereof, Section VII: Plastics and Articles Thereof; Rubber and Articles Thereof, used by U.S. Customs and Border Protection to determine the duty rate at entry. No Chapter 99 tariff modifications (Section 301, Section 232, IEEPA) or AD/CVD orders currently flag this code in Tandom's catalog.
New to HTS codes? Read our guide on how HTS classification works →
Past CBP decisions classifying real products under this HTS code. Useful precedent when classifying a similar product — each ruling shows how CBP interpreted the code for a specific case.
The tariff classification of methyl methacrylate-butadeine-styrene copolymers (CAS-25053-09-2) from Korea
The tariff classification of various methyl methacrylate-butadiene-styrene (MBS) copolymers from South Korea. Correction to Ruling Number N196116.
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 3903.90.10.00 is the U.S. Harmonized Tariff Schedule classification for Polymers of styrene, in primary forms, methyl methacrylate-butadiene-styrene (MBS) copolymers. It belongs to Chapter 39 of the HTSUS.
The general (Column 1) duty rate for HTS 3903.90.10.00 is 6.5%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 3903.90.10.00 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free (A,AU,BH,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 3903.90.10.00 is 15.4¢/kg + 67.5%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 3903.90.10.00 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
No active AD/CVD orders currently flag HTS 3903.90.10.00 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
Free Trade Agreement and special-program eligibility
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