HS 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

Published: 2026-05-08 Reviewed: 2026-05-08 Authority: WCO HS 2022 + DJBC BTKI chapter structure

Field	Value
Code	3913
Level	Heading / 4 digits
Chapter	Chapter 39
Section	Plastics and rubber
6-digit subheadings	2
Branch groups	0

Practical summary

Heading 3913 sits inside chapter 39 and groups a product family before you select the more specific 6-digit subheading. This layer uses the WCO 2022 nomenclature as the structural base and routes you back to Indonesia’s BTKI for final customs decisions.

6-digit subheadings

Code	Title	Route
391310	Alginic acid, its salts and esters	391310
391390	Other	391390

How to use this page

Use this heading to lock the product family, then move down to the 6-digit subheading before checking any more specific Indonesian tariff line. If the product is still ambiguous, re-check its technical specification, composition, and function against the official BTKI/INSW tools.

Sources

Source	URL	Coverage	Tier
WCO HS 2022	https://www.wcotradetools.org/en/harmonized-system/search/2022/en	4-digit headings and 6-digit subheadings	official
DJBC BTKI	https://www.beacukai.go.id/btki-dan-tarif	Indonesia chapter mapping and BTKI context	official
INSW tariff lookup	https://insw.go.id/intr	Existing Indonesian tariff-line examples	official

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