Electrical transformers — HTS 8504
Electrical transformers, static converters (for example, rectifiers) and inductors; parts thereof
Chapter 85 › Heading 8504
2026 HTS Rev 19 Synced Rules verified Operational
Written to help non-specialists understand this page. Rates, dates, and legal facts come from the official records above and on the linked source.
HTS heading 8504 groups electrical equipment that transfers, converts, or controls electrical energy without using moving parts. It includes transformers, static converters such as rectifiers, and inductors, along with certain parts. A transformer generally changes voltage or current; a static converter changes electricity from one form to another, such as AC to DC; and an inductor stores energy in a magnetic field and resists changes in current.
Heading 8504 is only a 4-digit category, not the final classification. To reach the applicable 8-digit HTSUS subheading, identify the product’s principal function, construction, and technical type, then follow the more specific branch for that type. Depending on the item, the distinctions may involve the equipment’s design or capacity, whether it is a complete article or a part, and other wording in the subheading and statistical provisions. Confirm the current HTSUS text and any applicable notes before entry.
What to check
- Identify whether the item is primarily a transformer, static converter, inductor, or a part, and describe its electrical function in technical terms.
- Check product specifications such as input and output voltage, current, power rating, frequency, phase, and whether it converts AC, DC, or both.
- Read every subheading under 8504 in sequence; do not choose an 8-digit code based only on a product name, marketing label, or battery-charger description.
- Determine whether the imported item is a complete unit, an identifiable part, or a general-purpose component that may be classified elsewhere.
- Compare the candidate code with the HTSUS legal notes, unit-of-measure requirements, and current customs guidance; ask a customs broker or request a binding ruling when the technical distinctions are uncertain.
HTS heading 8504 summary
Electrical transformers is a 4-digit product category containing 1 published product-code lines in this snapshot. A heading does not carry one universal duty rate; classification must be narrowed to the line matching the product facts.
How to find your code in this category
A heading is a product category. To get the exact duty, narrow from this 4-digit heading to a sub-category (usually by material), then open the 8-digit code that matches your product.
Open any code in the tables below to see its exact duty rate, a duty calculator (enter your shipment value → estimated duty and landed cost), the rate-change history chart, and the country-by-country breakdown (including Section 301/232 add-on duties).
Why you have to click in: a single category can contain products with very different duties. The rate depends on the specific product — its material and construction — and on the country of origin, and those only get pinned down at the 8-digit code level. That is why this page points you to codes instead of showing one rate for the whole category.
Sub-categories
| Code | Description |
|---|---|
| 8504.40 | Static converters |
| 8504.50 | Other inductors |
| 8504.90 | Parts |
Product codes & duty rates
👇 Each row is a specific product code — click a blue code to open its full page with exact duty rates by country, the rate-history chart, and a duty calculator. 👉
| Code | Description | General (MFN) | Special | Column 2 |
|---|---|---|---|---|
| 8504.10.00.00 👉 | Ballasts for discharge lamps or tubes | 3% | Free | 35% |
"Special" shows the free-trade-agreement rate; open a code to see exactly which countries qualify.
Common questions
What products fall under HTS heading 8504?
Electrical transformers, static converters (for example, rectifiers) and inductors; parts thereof. To classify a specific item you must pick the matching sub-category and 8-digit code above; the right choice usually depends on the material and construction of the product.
How do I choose the right code within this category?
Start from the sub-categories (typically divided by material—for example cotton versus man-made fibers), then open the active 8- or 10-digit code that matches the product. When unsure, a licensed customs broker or a CBP binding ruling can confirm the classification.
Reference information only, not customs, legal, or classification advice. Confirm the current code and rate against the official HTS before you import.