3105.51.00.00—Containing nitrates and phosphates
General
Free
Units
t
Column 2
Free
Special
—
Plain-English explanation
HTS 3105.51.00.00 is the U.S. Harmonized Tariff Schedule classification for Containing nitrates and phosphates. It's a 10-digit statistical line in Chapter 31: Fertilizers, Section VI: Products of the Chemical or Allied Industries, used by U.S. Customs and Border Protection to determine the duty rate at entry. 1 Chapter 99 tariff modification currently stacks on top of the base rate, and 2 active AD/CVD orders flag this code.
New to HTS codes? Read our guide on how HTS classification works →
Tariff modifications(1)
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.27.05 | other | 100% |
Potentially applicable AD/CVD orders(2)
Active orders that may apply to imports under this HTS code. HTS coverage is advisory — actual scope depends on each order's product description. Run the AD/CVD lookup → to check whether your specific shipment is in scope.
Recent CBP rulings(2)
Past CBP decisions classifying real products under this HTS code. Useful precedent when classifying a similar product — each ruling shows how CBP interpreted the code for a specific case.
The tariff classification of Nitric Phosphates Fertilizer (NP 33-3-0) from Russia
The tariff classification of NPK 33-3-00 from Russia.
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
Frequently asked questions
What is HTS code 3105.51.00.00?
HTS 3105.51.00.00 is the U.S. Harmonized Tariff Schedule classification for Containing nitrates and phosphates. It belongs to Chapter 31 of the HTSUS.
What is the general duty rate for HTS 3105.51.00.00?
The general (Column 1) duty rate for HTS 3105.51.00.00 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Are there Section 301 or Section 232 tariffs on HTS 3105.51.00.00?
Yes — HTS 3105.51.00.00 is covered by other provision 9903.27.05 (100%). Open the code page for the full overlay stack with effective dates and country scopes.
Does HTS 3105.51.00.00 have any antidumping or countervailing duty (AD/CVD) orders?
Yes — 2 AD/CVD orders flag this code: C-821-825 (CVD, Russia), C-714-001 (CVD, Morocco). Open the code page for deposit rates, scope determinations, and the linked case lookups.
Learn more
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