8504.40.70.18—Electrical transformers, static converters (for example, rectifiers) and inductors; parts thereof, static converters, otherGeneral
Free
Units
No.
Column 2
35%
Special
—
HTS 8504.40.70.18 is the U.S. Harmonized Tariff Schedule classification for Electrical transformers, static converters (for example, rectifiers) and inductors; parts thereof, static converters, other. It's a 10-digit statistical line in Chapter 85: Electrical machinery and equipment and parts thereof; sound recorders and reproducers; television image and sound recorders and reproducers, and parts and accessories of such articles, Section XVI: Machinery and Mechanical Appliances; Electrical Equipment; Parts Thereof; Sound Recorders and Reproducers, Television Image and Sound Recorders and Reproducers, and Parts and Accessories of Such Articles, used by U.S. Customs and Border Protection to determine the duty rate at entry. 2 Chapter 99 tariff modifications currently stack on top of the base rate.
New to HTS codes? Read our guide on how HTS classification works →
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.88.01 | section_301 | The duty provided in the applicable subheading plus 25% |
| 9903.88.15 | section_301 | The duty provided in the applicable subheading + 7.5% |
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 a power supply unit from China
The tariff classification of the StacoSine Active Harmonic Filter and the UniStar II Uninterruptible Power Supply (UPS) from China
The tariff classification of Uninterruptible Power Supplies (UPS) from an unspecified country
The tariff classification of Uninterruptible Power Supplies (UPS) from an unspecified country
The tariff classification of uninterruptible power supply systems from Taiwan
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 8504.40.70.18 is the U.S. Harmonized Tariff Schedule classification for Electrical transformers, static converters (for example, rectifiers) and inductors; parts thereof, static converters, other. It belongs to Chapter 85 of the HTSUS.
The general (Column 1) duty rate for HTS 8504.40.70.18 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
The Column 2 rate for HTS 8504.40.70.18 is 35%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
Yes — HTS 8504.40.70.18 is covered by section_301 provision 9903.88.01 (The duty provided in the applicable subheading plus 25%). 1 additional overlay also touch this code. Open the code page for the full overlay stack with effective dates and country scopes.
No active AD/CVD orders currently flag HTS 8504.40.70.18 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
Tandom guides relevant to this code
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.
Open resource
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.
Open resource
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.
Open resource
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.
Open resource
What changed April 6, 2026, what stayed the same, and how to file a steel, aluminum, or copper line in ACE without leaving duty exposure on the table.
Open resource
Where trade compliance APIs fit in a broker's filing pipeline: HTS classification, duty calculation, AD/CVD scope match, and post-summary corrections.
Open resource