Chapter notes
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
CHAPTER 31
FERTILIZERS
VI
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Notes
1. This chapter does not cover:
(a) Animal blood of heading 0511;
(b) Separate chemically defined compounds (other than those answering to the descriptions in note 2(a), 3(a), 4(a) or 5, below);
or
(c) Cultured potassium chloride crystals (other than optical elements) weighing not less than 2.5 g each, of heading 3824; optical
elements of potassium chloride (heading 9001).
2. Heading 3102 applies only to the following goods, provided that they are not put up in the forms or packages described in heading
3105:
(a) Goods which answer to one or other of the descriptions given below:
(i) Sodium nitrate, whether or not pure;
(ii) Ammonium nitrate, whether or not pure;
(iii) Double salts (whether or not pure) of ammonium sulfate and ammonium nitrate;
(iv) Ammonium sulfate, whether or not pure;
(v) Double salts (whether or not pure) or mixtures of calcium nitrate and ammonium nitrate;
(vi) Double salts (whether or not pure) or mixtures of calcium nitrate and magnesium nitrate;
(vii) Calcium cyanamide, whether or not pure or treated with oil;
(viii)Urea, whether or not pure.
(b) Fertilizers consisting of any of the goods described in (a) above mixed together.
(c) Fertilizers consisting of ammonium chloride or of any of the goods described in (a) or (b) above mixed with chalk, gypsum
or other inorganic nonfertilizing substances.
(d) Liquid fertilizers consisting of the goods of subparagraph (a)(ii) or (a)(viii) above, or of mixtures of those goods, in an aqueous
or ammoniacal solution.
3. Heading 3103 applies only to the following goods, provided that they are not put up in the forms or packages described in heading
3105:
(a) Goods which answer to one or other of the descriptions given below:
(i) Basic slag;
(ii) Natural phosphates of heading 2510, calcined or further heat-treated than for the removal of impurities;
(iii) Superphosphates (single, double or triple);
(iv) Calcium hydrogenorthophosphate containing not less than 0.2 percent by weight of fluorine calculated on the dry
anhydrous product.
(b) Fertilizers consisting of any of the goods described in (a) above, mixed together, but with no account being taken of the
fluorine content limit.
(c) Fertilizers consisting of any of the goods described in (a) or (b) above, but with no account being taken of the fluorine content
limit, mixed with chalk, gypsum or other inorganic nonfertilizing substances.
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
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Notes (con.)
4. Heading 3104 applies only to the following goods, provided that they are not put up in the forms or packages described in heading
3105:
(a) Goods which answer to one or other of the descriptions given below:
(i) Crude natural potassium salts (for example, carnallite, kainite and sylvite);
(ii) Potassium chloride, whether or not pure, except as provided in note 1(c) above;
(iii) Potassium sulfate, whether or not pure;
(iv) Magnesium potassium sulfate, whether or not pure.
(b) Fertilizers consisting of any of the goods described in (a) above mixed together.
5. Ammonium dihydrogenorthophosphate (monoammonium phosphate) and diammonium hydrogenorthophosphate (diammonium
phosphate), whether or not pure, and intermediates thereof, are to be classified in heading 3105.
6. For the purposes of heading 3105, the term "other fertilizers" applies only to products of a kind used as fertilizers and containing,
as an essential constituent, at least one of the fertilizing elements nitrogen, phosphorus or potassium.
Harmonized Tariff Schedule of the United States Revision 29 (2025)
Annotated for Statistical Reporting Purposes
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Section notes
SECTION VI
PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES
VI-1
Notes
1. (a) Goods (other than radioactive ores) answering to a description in heading 2844 or 2845 are to be classified in those headings
and in no other heading of the tariff schedule.
(b) Subject to paragraph (a) above, goods answering to a description in heading 2843, 2846 or 2852 are to be classified in those
headings and in no other heading of this section.
2. Subject to note 1 above, goods classifiable in heading 3004, 3005, 3006, 3212, 3303, 3304, 3305, 3306, 3307, 3506, 3707 or
3808 by reason of being put up in measured doses or for retail sale are to be classified in those headings and in no other heading
of the tariff schedule.
3. Goods put up in sets consisting of two or more separate constituents, some or all of which fall in this section and are intended
to be mixed together to obtain a product of section VI or VII, are to be classified in the heading appropriate to that product,
provided that the constituents are:
(a) Having regard to the manner in which they are put up, clearly identifiable as being intended to be used together without first
being repacked;
(b) Entered together; and
(c) Identifiable, whether by their nature or by the relative proportions in which they are present, as being complementary one
to another.
4. Where a product answers to a description in one or more of the headings in section VI by virtue of being described by name or
function and also to heading 3827, then it is classifiable in a heading that references the product by name or function and not
under heading 3827.
Additional U.S. Notes
1. In determining the amount of duty applicable to a solution of a single compound in water subject to duty in this section at a specific
rate, an allowance in weight or volume, as the case may be, shall be made for the water in excess of any water of crystallization
which may be present in the undissolved compound.
2. For the purposes of the tariff schedule:
(a) The term "aromatic" as applied to any chemical compound refers to such compound containing one or more fused or unfused
benzene rings;
(b) The term "modified aromatic" describes a molecular structure having at least one six-membered heterocyclic ring which
contains at least four carbon atoms and having an arrangement of molecular bonds as in the benzene ring or in the quinone
ring, but does not include any such molecular structure in which one or more pyrimidine rings are the only modified aromatic
rings present;
(c) For the purposes of headings 2902, 2907 and 3817, the term "alkyl" describes any saturated acyclic hydrocarbon group
having six or more carbon atoms or, subject to note 1 to
