3105.51.00.00—Containing nitrates and phosphates
General
Free
Units
t
Column 2
Free
Special
—
3105.51.00.00—Containing nitrates and phosphatesGeneral
Free
Units
t
Column 2
Free
Special
—
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 →
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.27.05 | other | 100% |
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.
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 →)
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.
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.
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.
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.
Tandom guides relevant to this code
Where trade compliance APIs fit in a broker's filing pipeline: HTS classification, duty calculation, AD/CVD scope match, and post-summary corrections.
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How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
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A working guide to the inputs, the layers, and the math behind a US entry summary in 2026. Written for brokers, forwarders, and importer compliance teams.
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Drop the Tandom Duty Calculator API into a TMS, broker software, or in-house ERP. Code samples, the response shape, and ACE reporting order, in 2026.
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What the 178 active Section 301 exclusions cover, how to claim 9903.88.69 on an entry, and what changes when the November 10, 2026 deadline passes.
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