HTS heading 3913
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 — 8 codes under this heading, with the duty on each.
| Code | Description | General rate | Units |
|---|---|---|---|
| 3913 | 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 + Ch. 99 | not stated | — |
| 3913.10.00.00 | Alginic acid, its salts and esters + Ch. 99 | 4.2% | kg |
| 3913.90 | Other + Ch. 99 | not stated | — |
| 3913.90.10.00 | Chemical derivatives of natural rubber + Ch. 99 | Free | kg |
| 3913.90.20 | Polysaccharides and their derivatives + Ch. 99 | 5.8% | — |
| 3913.90.20.15 | Xanthan gum + Ch. 99 | 5.8% (inherited from 3913.90.20) | kg |
| 3913.90.20.90 | Other + Ch. 99 | 5.8% (inherited from 3913.90.20) | kg |
| 3913.90.50.00 | Other + Ch. 99 | 6.5% | kg |
2 of these lines state no rate of their own and inherit one from the line above, which is how the schedule is read. Each says which line it came from.
Additional duties may apply
8 lines here reference Chapter 99, where Section 301, Section 232 and other additional duties live. Those are charged on top of the general rate and depend on where the goods were made. What those provisions are.
Source: Harmonized Tariff Schedule of the United States, U.S. International Trade Commission (public domain). Classification and the duties that finally apply to a shipment are a licensed customs broker's call.