HTS heading 3913: Natural polymers (for example, alginic acid) and modified natural polymers (for example, hardened proteins, chemical derivatives of natural rubber), not elsewhe
Heading 3913 of the US Harmonized Tariff Schedule covers 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. Below: every rated tariff line in it with its general duty rate, Section 301 China status and exclusions, then a page per line with a free duty calculator.
Heading 3913 at a glance
- 4 rated tariff lines; 1 duty-free at the general (MFN) rate.
- Ad valorem general rates from 4.2% to 6.5%.
- Section 301 (products of China): 4 of 4 lines on a list in effect (List 2, List 3, List 4A).
- 1 Section 301 product exclusion in effect for heading 3913; each is listed on its line page with its end date.
Goods named in this heading (official line texts): Alginic acid, its salts and esters, Chemical derivatives of natural rubber, Polysaccharides and their derivatives.
Subheadings (6-digit)
All tariff lines in heading 3913
| Line | Description | General | Section 301 (China) | Exclusions |
|---|---|---|---|---|
| 3913.10.00 | Alginic acid, its salts and esters | 4.2% | List 4A +7.5% (1 product exclusion may apply) | 1 |
| 3913.90.10 | Chemical derivatives of natural rubber | Free | List 2 +25% | |
| 3913.90.20 | Polysaccharides and their derivatives | 5.8% | List 3 +25% | |
| 3913.90.50 | Other: Other | 6.5% | List 2 +25% |
All of chapter 39 · Chapter 39 rate summary · HTS lookup
General information from the official US Harmonized Tariff Schedule (USITC) and USTR Section 301 notices in HTS Chapter 99; not legal or customs advice. Classification is decided by CBP; confirm with a licensed customs broker or a CBP binding ruling.
🔔 Get a browser alert when US tariffs change (free, no email, one click to stop).