Chapter 39 covers plastics and articles thereof, including polymers in primary forms, synthetic resins, chemically modified natural polymers, etc. This chapter is classified by polymer source and chemical structure, divided into primary forms, waste and scrap, semi-manufactures, tubes, sheets, etc. Primary forms refer to liquid, paste, block, powder and other unshaped states, and are the general term for plastic raw materials. Heading 3912 covers cellulose and its chemical derivatives, in primary forms, not elsewhere specified or included. It specifically covers carboxymethyl cellulose (CMC), hydroxyethyl cellulose, methyl cellulose and other cellulose ethers and esters, as well as regenerated cellulose, cellulose nitrate, etc. Note that synthetic resins such as ethylene polymers are not included. First 2 digits 39: Chapter 39 plastics and articles thereof. Digits 3-4, 12: heading 3912, cellulose and its chemical derivatives, in primary forms. Digits 5-6, 31: subheading 391231, carboxymethyl cellulose (CMC) and its salts, in primary forms. The complete code 391231 means carboxymethyl cellulose and its salts in primary forms. Carboxymethyl cellulose is a chemical derivative of cellulose (ether type), not a synthetic resin, so it is classified under 3912 rather than 3901-3911. Its primary forms (powder, granules, etc.) meet subheading 391231; if it is an article, it is classified under other subheadings of 3912 or subsequent headings of Chapter 39.
Chapter
Chapter 39 covers plastics and articles thereof, including polymers in primary forms, synthetic resins, chemically modified natural polymers, etc. This chapter is classified by polymer source and chemical structure, divided into primary forms, waste and scrap, semi-manufactures, tubes, sheets, etc. Primary forms refer to liquid, paste, block, powder and other unshaped states, and are the general term for plastic raw materials.
Heading
Heading 3912 covers cellulose and its chemical derivatives, in primary forms, not elsewhere specified or included. It specifically covers carboxymethyl cellulose (CMC), hydroxyethyl cellulose, methyl cellulose and other cellulose ethers and esters, as well as regenerated cellulose, cellulose nitrate, etc. Note that synthetic resins such as ethylene polymers are not included.
Digit Breakdown
First 2 digits 39: Chapter 39 plastics and articles thereof. Digits 3-4, 12: heading 3912, cellulose and its chemical derivatives, in primary forms. Digits 5-6, 31: subheading 391231, carboxymethyl cellulose (CMC) and its salts, in primary forms. The complete code 391231 means carboxymethyl cellulose and its salts in primary forms.
Classification Basis
Carboxymethyl cellulose is a chemical derivative of cellulose (ether type), not a synthetic resin, so it is classified under 3912 rather than 3901-3911. Its primary forms (powder, granules, etc.) meet subheading 391231; if it is an article, it is classified under other subheadings of 3912 or subsequent headings of Chapter 39.
📝 Declaration Elements
Product name: Declared commodity name should specifically be carboxymethyl cellulose (CMC) or sodium carboxymethyl cellulose, etc. Appearance: Describe the primary form, such as white powder, granules, fibrous, etc.; it must not be in the form of an article. Composition and content: Indicate carboxymethyl cellulose content, moisture, salt content (such as sodium content), etc.; purity affects classification. Grade: Industrial grade, food grade, pharmaceutical grade, etc.; different grades have different uses but the same classification. Packaging specifications: Such as 25kg/bag, 500kg/jumbo bag; affects whether it is retail packaging. Use: Such as oil drilling, food thickening, pharmaceutical excipients, etc.; use does not affect classification but must be declared. Brand or model: If there is a brand or model, it must be declared; if there is no brand, 'none' may be filled in. Product name: sodium carboxymethyl cellulose (CMC); Appearance: white powder; Composition and content: sodium carboxymethyl cellulose ≥99%, moisture ≤10%; Grade: industrial grade; Packaging specifications: 25kg/bag; Use: thickener for oil drilling fluid; Brand: none; Model: FV-100. Confusing carboxymethyl cellulose with methyl cellulose, the latter being classified under 391239. Mistakenly declaring an aqueous CMC solution as a primary form, when it should actually be classified under other headings. Failure to distinguish between the sodium salt and the free acid; the free acid is also classified under 391231 but must be indicated. Classifying food-grade CMC under Chapter 35 or Chapter 29, ignoring its polymer properties.
Product name
Declared commodity name should specifically be carboxymethyl cellulose (CMC) or sodium carboxymethyl cellulose, etc.
⚠️ Writing only 'cellulose' or 'CMC' without specifying the specific derivative name.
Appearance
Describe the primary form, such as white powder, granules, fibrous, etc.; it must not be in the form of an article.
⚠️ Declaring it as a 'solution' when it is actually an aqueous solution, which may be classified under other chapters.
Composition and content
Indicate carboxymethyl cellulose content, moisture, salt content (such as sodium content), etc.; purity affects classification.
⚠️ Failure to indicate the salt type (sodium salt, potassium salt) or purity, leading to confusion among subheadings.
Grade
Industrial grade, food grade, pharmaceutical grade, etc.; different grades have different uses but the same classification.
⚠️ Mistakenly classifying food grade under food chapters.
Packaging specifications
Such as 25kg/bag, 500kg/jumbo bag; affects whether it is retail packaging.
⚠️ Retail packaging may affect classification, but primary forms usually do not change classification due to packaging.
Use
Such as oil drilling, food thickening, pharmaceutical excipients, etc.; use does not affect classification but must be declared.
⚠️ Use description is too broad, such as 'industrial use'.
Brand or model
If there is a brand or model, it must be declared; if there is no brand, 'none' may be filled in.
⚠️ Omitting the brand leads to an incomplete customs declaration form.
Confusing carboxymethyl cellulose with methyl cellulose, the latter being classified under 391239.
Mistakenly declaring an aqueous CMC solution as a primary form, when it should actually be classified under other headings.
Failure to distinguish between the sodium salt and the free acid; the free acid is also classified under 391231 but must be indicated.
Classifying food-grade CMC under Chapter 35 or Chapter 29, ignoring its polymer properties.
🎯 Classification Logic
Core basis for classification: 1) the goods are chemical derivatives of cellulose (ether type); 2) primary forms (powder, granules, etc., unshaped); 3) specifically carboxymethyl cellulose and its salts. According to HS notes, 3912 includes cellulose ethers, and subheading 391231 specifically refers to CMC. If it is an article (such as film, tube), it is classified under later subheadings of 3912 or other headings of Chapter 39. 391239 Other cellulose ethers: 391239 covers methyl cellulose, hydroxyethyl cellulose, etc., while 391231 refers only to carboxymethyl cellulose and its salts. The core difference lies in the different chemical substituents. 391290 Other cellulose and its chemical derivatives: 391290 includes cellulose esters (such as cellulose nitrate) and other derivatives not elsewhere specified, while 391231 specifically refers to CMC. If CMC is mixed with other substances, it may be classified under 391290. 350510 Dextrins and other modified starches: 350510 is modified starch; although it is also a thickener, its source is different. CMC is a cellulose derivative and is classified under Chapter 39. 290511 Methanol: 290511 is a separate chemical substance, while CMC is a polymer and is classified under Chapter 39. If it is methanol as a raw material for CMC, it is classified under Chapter 29. 382499 Other chemical industry products: 382499 is miscellaneous chemicals. If CMC is formulated into a specialized product, it may be classified under this code, but pure CMC is still classified under 391231. Is it indeed carboxymethyl cellulose and its salts? Is it in primary forms (powder, granules, etc.)? Is it mixed with other substances? Is it used for a specific purpose that changes classification? Is it distinguished from adjacent subheadings 391239 and 391290?
Basis
Core basis for classification: 1) the goods are chemical derivatives of cellulose (ether type); 2) primary forms (powder, granules, etc., unshaped); 3) specifically carboxymethyl cellulose and its salts. According to HS notes, 3912 includes cellulose ethers, and subheading 391231 specifically refers to CMC. If it is an article (such as film, tube), it is classified under later subheadings of 3912 or other headings of Chapter 39.
Confused Codes：
391239 - Other cellulose ethers
391239 covers methyl cellulose, hydroxyethyl cellulose, etc., while 391231 refers only to carboxymethyl cellulose and its salts. The core difference lies in the different chemical substituents.
391290 - Other cellulose and its chemical derivatives
391290 includes cellulose esters (such as cellulose nitrate) and other derivatives not elsewhere specified, while 391231 specifically refers to CMC. If CMC is mixed with other substances, it may be classified under 391290.
350510 - Dextrins and other modified starches
350510 is modified starch; although it is also a thickener, its source is different. CMC is a cellulose derivative and is classified under Chapter 39.
290511 - Methanol
290511 is a separate chemical substance, while CMC is a polymer and is classified under Chapter 39. If it is methanol as a raw material for CMC, it is classified under Chapter 29.
382499 - Other chemical industry products
382499 is miscellaneous chemicals. If CMC is formulated into a specialized product, it may be classified under this code, but pure CMC is still classified under 391231.
Self-Check：
✓ Is it indeed carboxymethyl cellulose and its salts?
✓ Is it in primary forms (powder, granules, etc.)?
✓ Is it mixed with other substances?
✓ Is it used for a specific purpose that changes classification?
✓ Is it distinguished from adjacent subheadings 391239 and 391290?
❓ FAQ
What is the difference in HS codes between carboxymethyl cellulose (CMC) and sodium carboxymethyl cellulose (NaCMC)? Both are classified under 391231, because the subheading covers carboxymethyl cellulose and its salts. When declaring, it is necessary to indicate whether it is the acid type or sodium salt, but the code is the same. How can I check the import tax rate for 391231? It can be checked through the official website of the General Administration of Customs, the International Trade Single Window, or the 'Import and Export Tariff of the People's Republic of China'. Tax rates may change, so it is recommended to rely on the latest tariff. Which code should an aqueous CMC solution be classified under? If CMC is declared in the form of an aqueous solution and water is the solvent, it is usually still classified under 391231; however, if the solution is a dispersion or emulsion, it may be classified under other headings. It is recommended to declare it as a primary form. Are the codes for food-grade CMC and industrial-grade CMC the same? Yes, both are classified under 391231. However, food grade must comply with food safety standards, and relevant certificates must be provided at declaration; the code does not change due to grade. How should CMC mixed with other cellulose ethers be classified? If CMC remains the main component after mixing, it may be classified under 391231; if it is a mixture of multiple ethers, it is classified under 391239 or 391290. Judgment should be based on composition and use. How should the declaration element 'Composition and content' be filled in during customs declaration? It should include the purity, moisture, salt content, etc. of CMC. For example, 'sodium carboxymethyl cellulose ≥99%, moisture ≤10%'. Purity affects classification and must be accurate. If CMC is used for oil drilling, is it classified under Chapter 38? No, pure CMC is still classified under 391231. If it is formulated into a drilling fluid additive, it may be classified under 3824, but when CMC is declared separately, it is under 391231. For cross-border e-commerce sales of small packages of CMC, does the code change? The code does not change; it remains 391231. However, if the small package is retail packaging, attention should be paid to whether it affects classification; primary forms usually do not change due to packaging.
Q: What is the difference in HS codes between carboxymethyl cellulose (CMC) and sodium carboxymethyl cellulose (NaCMC)?
A: Both are classified under 391231, because the subheading covers carboxymethyl cellulose and its salts. When declaring, it is necessary to indicate whether it is the acid type or sodium salt, but the code is the same.
Q: How can I check the import tax rate for 391231?
A: It can be checked through the official website of the General Administration of Customs, the International Trade Single Window, or the 'Import and Export Tariff of the People's Republic of China'. Tax rates may change, so it is recommended to rely on the latest tariff.
Q: Which code should an aqueous CMC solution be classified under?
A: If CMC is declared in the form of an aqueous solution and water is the solvent, it is usually still classified under 391231; however, if the solution is a dispersion or emulsion, it may be classified under other headings. It is recommended to declare it as a primary form.
Q: Are the codes for food-grade CMC and industrial-grade CMC the same?
A: Yes, both are classified under 391231. However, food grade must comply with food safety standards, and relevant certificates must be provided at declaration; the code does not change due to grade.
Q: How should CMC mixed with other cellulose ethers be classified?
A: If CMC remains the main component after mixing, it may be classified under 391231; if it is a mixture of multiple ethers, it is classified under 391239 or 391290. Judgment should be based on composition and use.
Q: How should the declaration element 'Composition and content' be filled in during customs declaration?
A: It should include the purity, moisture, salt content, etc. of CMC. For example, 'sodium carboxymethyl cellulose ≥99%, moisture ≤10%'. Purity affects classification and must be accurate.
Q: If CMC is used for oil drilling, is it classified under Chapter 38?
A: No, pure CMC is still classified under 391231. If it is formulated into a drilling fluid additive, it may be classified under 3824, but when CMC is declared separately, it is under 391231.
Q: For cross-border e-commerce sales of small packages of CMC, does the code change?
A: The code does not change; it remains 391231. However, if the small package is retail packaging, attention should be paid to whether it affects classification; primary forms usually do not change due to packaging.
⚠️ Disclaimer: HS code classification, declaration elements, tariff rates and regulatory conditions on this page are for reference only and do not constitute legal advice on customs classification. Tariff rates and regulations are subject to change; the latest announcements from the General Administration of Customs and on-site determinations shall prevail. Please consult professional customs brokers or customs authorities before import/export.