HS Code 3913Natural polymers (e.g. alginic acid) and modified natural polymers (e.g. hardened proteins, chemical derivatives of natural rubber), n.e.c. or included, in primary forms
2 six-digit codes · Heading 13 of 26 in Chapter 39 · World Customs Organization Harmonized System
HS code 3913 is the heading for natural polymers like alginic acid, and for natural polymers that chemistry has changed. This page shows how to pick between its two subheadings and how it differs from the headings next to it.
The WCO writes heading 3913 as a residual bucket: goods of Chapter 39that answer to “Natural polymers (e.g. alginic acid) and modified natural polymers (e.g. hardened proteins, chemical derivatives of natural rubber), n.e.c. or included, in primary forms” and that no more specific heading in the chapter already claims. It still carries 2 six-digit codes, 391310 through 391390, so “other” is not the end of the classification here. The heading is number 13 of 26 in Chapter 39, Plastics and articles thereof, which runs to 131 six-digit codes in all.
What this heading covers
Heading 3913 is the home for natural polymers that no other heading in plastics names. A polymer is a long chain molecule. A natural polymer is one that nature makes. Alginic acid is the first example the heading gives.
The heading also takes modified natural polymers. These start as a natural material and are then altered with chemistry.
Two limits matter. First, the goods must be in primary forms. That means the polymer as a base material, not a finished article. Second, n.e.c. means not elsewhere classified. If a product has a more specific home in the chapter, it goes there instead.
Six-digit codes under 3913: 391310 vs 391390
Choosing the subheading comes down to one question. Is the product alginic acid, or a salt or ester of it? If yes, use 391310. Salts and esters of alginic acid are often called alginates.
If the product is any other natural or modified natural polymer in primary forms, use 391390. This is the catch-all line. Alginic acid and its salts and esters are the only goods it leaves out.
The classification path runs from Section VII to Chapter 39, then to heading 3913, then to one of the two subheadings. It follows the WCO Harmonized System, the shared base for tariff classification. Each country adds its own digits after the sixth. Duty is set at that national tariff line, not at 3913 itself. If you are unsure where a product belongs, try the HS code classifier.
3913 vs nearby headings 3911, 3912 and 3914
Cellulose is a natural polymer too, but it has its own heading, so it stays out of 3913. A natural polymer that is neither cellulose nor alginic acid is a 3913 candidate.
Heading 3911 is for resins made by chemical synthesis. It lists petroleum resins, coumarone-indene resins, polyterpenes, polysulphides and polysulphones. These are built in a plant from other chemicals. They are not natural materials that were later modified.
Heading 3914 is for ion-exchangers based on the polymers of headings 3901 to 3913. A 3913 polymer can be the base of a 3914 product, but the two headings are different.
Rubber needs a note. Only chemical derivatives of natural rubber, in primary forms, fit under 3913.
HS code 3913 import and export data
Once you know the code, the next question is who trades it. You can search by HS code to see who imports and exports a product.
EximDataX shows shipment-level import and export records from official customs sources. Coverage: 43 direct customs feeds plus 184 mirror-derived countries. Named buyers and named suppliers are available in 38 of the 43 direct markets. Most markets refresh weekly and some refresh daily.
Search 3913, 391310 or 391390 to see live shipment records by country. You can also book a free demo.
Related
- Chapter 39: plastics and articles thereof
- HS 3912 cellulose and its derivatives
- HS 3911 petroleum resins and polysulphones
- HS 3914 ion-exchangers
- HS 3910 silicones in primary forms
- All HS code chapters
- HS 3913 import data
- HS 3913 export data
- Natural polymer buyers
- Natural polymer suppliers
- HS code classifier
- Book a free demo
Nearby headings in Chapter 39
- 3907Polyacetals, other polyethers and epoxide resins, in primary forms…11 codes
- 3908Polyamides in primary forms2 codes
- 3909Amino-resins, phenolic resins and polyurethanes, in primary forms6 codes
- 3910Silicones in primary forms1 code
- 3911Petroleum resins, coumarone-indene resins, polyterpenes, polysulphides…3 codes
- 3912Cellulose and its chemical derivatives, n.e.c. or included, in primary forms6 codes
- 3914Ion-exchangers; based on polymers of heading no. 3901 to 3913, in primary…1 code
- 3915Waste, parings and scrap, of plastics4 codes
- 3916Monofilament of which any cross-sectional dimension exceeds 1mm, rods, sticks…3 codes
- 3917Tubes, pipes and hoses and fittings thereof (for example, joints, elbows…10 codes
- 3918Floor coverings of plastics, self-adhesive or not, in rolls or tiles; wall or…2 codes
- 3919Self-adhesive plates, sheets, film, foil, tape, strip and other flat shapes…2 codes
Who ships under 3913?
EximDataX tracks the live import–export records filed under this heading and the 2 codes beneath it: named buyers, suppliers, quantities and values from official customs feeds.
Section VII: Plastics and Rubber, and Articles Thereof, chapters 39–40.
HS Code 3913: common questions
What is HS code 3913?
Alginic acid, hardened proteins and chemical derivatives of natural rubber are the examples it gives.
What is the HS code for alginic acid?
Use 391310.
What does HS code 391390 cover?
Use it when the product is not alginic acid or one of its salts or esters.
What is the difference between HS 3912 and 3913?
3912 is for cellulose and its chemical derivatives. 3913 takes other natural and modified natural polymers, such as alginic acid and hardened proteins.
Are chemical derivatives of natural rubber classified under 3913?
Yes, the heading lists them as an example of modified natural polymers. They must be in primary forms and not named in a more specific heading.
Where can I find importers and exporters for this heading?
Use the EximDataX import data and export data pages, then search by the heading or by 391310 or 391390. The buyer data and supplier data pages show the named parties.
See what your buyers are buying.Then decide.
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