Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 3913.10.00.00 is the U.S. Harmonized Tariff Schedule classification for Alginic acid, its salts and esters. 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. 3 Chapter 99 tariff modifications currently stack on top of the base rate.
New to HTS codes? Read our guide on how HTS classification works →
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.88.01 | section_301 | The duty provided in the applicable subheading plus 25% |
| 9903.88.15 | section_301 | The duty provided in the applicable subheading + 7.5% |
| 9903.88.69 | section_301 | The duty provided in the applicable subheading |
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 classifications of xanthan gum, sodium alginate, calcium lactate, soy lecithin, agar-agar, metal spoons and plastic utensils from various countries.
The tariff classification of Manucol Ester B from the Netherlands
Classification of Propylene Glycol Alginate
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 3913.10.00.00 is the U.S. Harmonized Tariff Schedule classification for Alginic acid, its salts and esters. It belongs to Chapter 39 of the HTSUS.
The general (Column 1) duty rate for HTS 3913.10.00.00 is 4.2%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 3913.10.00.00 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 3913.10.00.00 is 25%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
Yes — HTS 3913.10.00.00 is covered by section_301 provision 9903.88.01 (The duty provided in the applicable subheading plus 25%). 2 additional overlays also touch this code. Open the code page for the full overlay stack with effective dates and country scopes.
No active AD/CVD orders currently flag HTS 3913.10.00.00 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
Tandom guides relevant to this code
What the 178 active Section 301 exclusions cover, how to claim 9903.88.69 on an entry, and what changes when the November 10, 2026 deadline passes.
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How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
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A working guide to the inputs, the layers, and the math behind a US entry summary in 2026. Written for brokers, forwarders, and importer compliance teams.
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