3913
4-digit headingNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms
This is a 4-digit heading — a category, not a filing code. Pick the more specific code beneath it that best matches your goods; only a 10-digit statistical code can be used on a customs entry.
Duty rates
No rate is published at this level — check the specific 10-digit statistical code beneath it.
| Rate | Value and what it means |
|---|---|
| General rate (Column 1) | See 10-digit codeColumn 1 general Applies to most trading partners — the standard "normal trade relations" rate. |
| Special rate (Column 1) | —Trade programs The country letters in parentheses are free trade agreement and preference programs. If your goods qualify under one of them, that rate replaces the general rate. |
| Column 2 rate | —Non-NTR Reserved for the small group of countries that do not have normal trade relations with the US (currently Cuba, North Korea, Russia and Belarus). Almost no importer uses this column — if you are shipping from anywhere else, ignore it. |
| Unit of quantity | — How CBP expects the quantity to be reported on the entry summary. |
Codes within Natural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms
7 more specific lines fall under 3913.
- 3913.10.00.00Alginic acid, its salts and esters10-digit statistical codeNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms:4.2%
- 3913.90Other6-digit headingNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms:
- 3913.90.10.00Chemical derivatives of natural rubber10-digit statistical codeNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms: > Other:Free
- 3913.90.20Polysaccharides and their derivatives8-digit subheadingNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms: > Other:5.8%
- 3913.90.20.15Xanthan gum10-digit statistical codeNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms: > Other: > Polysaccharides and their derivatives
- 3913.90.20.90Other10-digit statistical codeNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms: > Other: > Polysaccharides and their derivatives
- 3913.90.50.00Other10-digit statistical codeNatural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhere specified or included, in primary forms: > Other:6.5%
Chapter 39: Plastics and Articles Thereof
Browse every code in this chapter to compare neighbouring classifications.
View Chapter 39Source: USITC Harmonized Tariff Schedule, 2026 Basic Edition, Revision 16. Rate text is reproduced verbatim from the official export; category paths and duty estimates are derived.
Data loaded August 18, 2026.Check this chapter on hts.usitc.govReport an error with this codeHow this data is built