Section VI: Products of the Chemical or Allied Industries
Chapter 31: Fertilizers
Chapter 31 of the U.S. Harmonized Tariff Schedule covers Fertilizers and sits within Section VI: Products of the Chemical or Allied Industries.
About Chapter 31
Chapter 31 contains 29 10-digit statistical lines grouped under 4 4-digit headings. Brokers, importers, and customs counsel use these codes to declare fertilizers on entry summaries (CBP Form 7501) and to look up the applicable Column 1, Special, and Column 2 duty rates.
All 29 10-digit lines in this chapter enter duty-free under the general (Column 1) rate. Country-of-origin overlays (Section 301 for China, Section 232 for steel/aluminum, IEEPA reciprocal tariffs, AD/CVD orders) can still apply on top of the base rate — open any code for the live overlay stack.
Every code page links into the Tandom Tariff Calculator with the HTS code prefilled, so you can compute the full landed duty for a specific shipment by entering value, country of origin, and (where relevant) material content or date of entry. Tandom's data refreshes daily from USITC HTSUS, CBP CSMS, the Federal Register, and the Department of Commerce — the same authoritative sources the trade community files against.
3101Animal or vegetable fertilizers, whether or not mixed together or chemically treated; fertilizers produced by the mixing or chemical treatment of animal or vegetable products
3101Animal or vegetable fertilizers, whether or not mixed together or chemically treated; fertilizers produced by the mixing or chemical treatment of animal or vegetable products| Code | Description | General | Column 2 | Special | Units |
|---|---|---|---|---|---|
| 3101.00.00.00 | Animal or vegetable fertilizers, whether or not mixed together or chemically treated; fertilizers produced by the mixing or chemical treatment of animal or vegetable products | Free | Free | — | t |
3102Mineral or chemical fertilizers, nitrogenous:
3102Mineral or chemical fertilizers, nitrogenous:| Code | Description | General | Column 2 | Special | Units |
|---|---|---|---|---|---|
| 3102.10.00 | Urea, whether or not in aqueous solution | Free | Free | — | — |
| 3102.10.00.10 | ·Solid urea | — | — | — | t |
| 3102.10.00.30 | ··Diesel exhaust fluid (DEF) of a kind meeting ISO 22241 | — | — | — | t |
| 3102.10.00.50 | ··Other | — | — | — | t |
| 3102.21.00.00 | ·Ammonium sulfate | Free | Free | — | t |
| 3102.29.00.00 | ·Other | Free | Free | — | t |
| 3102.30.00.00 | Ammonium nitrate, whether or not in aqueous solution | Free | Free | — | t |
| 3102.40.00.00 | Mixtures of ammonium nitrate with calcium carbonate or other inorganic nonfertilizing substances | Free | Free | — | t |
| 3102.50.00.00 | Sodium nitrate | Free | Free | — | t |
| 3102.60.00.00 | Double salts and mixtures of calcium nitrate and ammonium nitrate | Free | Free | — | t |
| 3102.80.00.00 | Mixtures of urea and ammonium nitrate in aqueous or ammoniacal solution | Free | Free | — | t |
| 3102.90.01.00 | Other, including mixtures not specified in the foregoing subheadings | Free | Free | — | t |
3103Mineral or chemical fertilizers, phosphatic:
3103Mineral or chemical fertilizers, phosphatic:| Code | Description | General | Column 2 | Special | Units |
|---|---|---|---|---|---|
| 3103.11.00.00 | ·Containing by weight 35 percent or more of diphosphorous pentaoxide (P2O5) | Free | Free | — | t |
| 3103.19.00.00 | ·Other | Free | Free | — | t |
| 3103.90.01.00 | Other | Free | Free | — | t |
3104Mineral or chemical fertilizers, potassic:
3104Mineral or chemical fertilizers, potassic:| Code | Description | General | Column 2 | Special | Units |
|---|---|---|---|---|---|
| 3104.20.00 | Potassium chloride | Free | Free | — | — |
| 3104.20.00.10 | ·Containing not more than 62 percent by weight of potassium oxide (K2O) | — | — | — | t |
| 3104.20.00.50 | ·Containing more than 62 percent by weight of potassium oxide (K2O) | — | — | — | t |
| 3104.30.00.00 | Potassium sulfate | Free | Free | — | t |
| 3104.90.01.00 | Other | Free | Free | — | t |
3105Mineral or chemical fertilizers containing two or three of the fertilizing elements nitrogen, phosphorus and potassium; other fertilizers; goods of this chapter in tablets or similar forms or in packages of a gross weight not exceeding 10 kg:
3105Mineral or chemical fertilizers containing two or three of the fertilizing elements nitrogen, phosphorus and potassium; other fertilizers; goods of this chapter in tablets or similar forms or in packages of a gross weight not exceeding 10 kg:| Code | Description | General | Column 2 | Special | Units |
|---|---|---|---|---|---|
| 3105.10.00.00 | Products of this chapter in tablets or similar forms or in packages of a gross weight not exceeding 10 kg | Free | Free | — | kg |
| 3105.20.00.00 | Mineral or chemical fertilizers containing the three fertilizing elements nitrogen, phosphorus and potassium | Free | Free | — | t |
| 3105.30.00.00 | Diammonium hydrogenorthophosphate (Diammonium phosphate) | Free | Free | — | t |
| 3105.40.00 | Ammonium dihydrogenorthophosphate (Monoammonium phosphate) and mixtures thereof with diammonium hydrogenorthophosphate (Diammonium phosphate) | Free | Free | — | — |
| 3105.40.00.10 | ·Ammonium dihydrogenorthophosphate (Monoammonium phosphate) | — | — | — | t |
| 3105.40.00.50 | ·Other | — | — | — | t |
| 3105.51.00.00 | ·Containing nitrates and phosphates | Free | Free | — | t |
| 3105.59.00.00 | ·Other | Free | Free | — | t |
| 3105.60.00.00 | Mineral or chemical fertilizers containing the two fertilizing elements phosphorus and potassium | Free | Free | — | t |
| 3105.90.00 | Other | Free | Free | — | — |
| 3105.90.00.10 | ·Potassium nitrate-sodium nitrate mixtures | — | — | — | t |
| 3105.90.00.50 | ·Other | — | — | — | t |
Frequently asked questions
What does HTS Chapter 31 cover?
Chapter 31 of the U.S. Harmonized Tariff Schedule (HTSUS) covers Fertilizers. It sits within Section VI: Products of the Chemical or Allied Industries. Tandom's catalog lists all 29 10-digit statistical lines and 4 4-digit headings in this chapter.
What is the typical U.S. duty rate for Chapter 31 imports?
Most lines in this chapter enter duty-free under the general (Column 1) rate. Use the calculator linked from each code page to compute the full landed rate, including Section 301/232 overlays, IEEPA tariffs, and AD/CVD deposits where applicable.
Are Section 301 or Section 232 tariffs applied to Chapter 31 products?
Section 301 (China) and Section 232 (steel, aluminum, copper) tariffs are layered on top of the base HTSUS rate via Chapter 99 provisions. Whether they apply to a specific 10-digit line in Chapter 31 depends on the product's country of origin, material content, and the active proclamation. Open any code in this chapter to see the live overlay stack and effective rate.
Are there antidumping or countervailing duty (AD/CVD) orders covering Chapter 31 products?
AD/CVD orders are issued at the case level by the Department of Commerce against specific products from specific countries. Tandom's AD/CVD catalog cross-references every active order to the HTS codes it covers — open any code in Chapter 31 to see flagged orders, deposit rates, and the underlying scope determinations.