Central heating boilers — HTS 8403
Central heating boilers (other than those of heading 8402) and parts thereof
Chapter 84 › Heading 8403
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 8403 is a broad product category for central-heating boilers, except boilers covered by heading 8402, and for identifiable parts of those boilers. It generally covers equipment designed to heat water or another medium for a central-heating system, rather than complete heating systems as a whole. The heading does not by itself establish the final duty treatment.
To reach the correct 8-digit HTSUS code, first confirm that the item belongs in heading 8403 and is not excluded by the heading 8402 distinction or another heading. Then use the relevant subheading descriptions, which may distinguish the boiler or part by features such as construction material, heating method, or whether it is a complete boiler or a part. The product’s function, design, and condition at import are important; a customs broker may be needed for close classification questions.
What to check
- Confirm that the product is a central-heating boiler or an identifiable part, not a boiler covered by heading 8402 or a component classified elsewhere.
- Read every subheading and statistical suffix under heading 8403, including distinctions based on material, type, function, or construction.
- Document the boiler’s fuel or heat source, intended use, capacity, operating method, and principal materials from technical specifications.
- For parts, verify that the item is principally or solely identifiable for use with an 8403 boiler and check whether another heading describes it more specifically.
- Compare the candidate 8-digit code with the current HTSUS, classification notes, and any applicable Customs rulings; request broker or specialist advice when the facts are ambiguous.
HTS heading 8403 summary
Central heating boilers is a 4-digit product category containing 2 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.
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 |
|---|---|---|---|---|
| 8403.10.00.00 👉 | Boilers | Free | — | 45% |
| 8403.90.00.00 👉 | Parts | Free | — | 45% |
"Special" shows the free-trade-agreement rate; open a code to see exactly which countries qualify.
Common questions
What products fall under HTS heading 8403?
Central heating boilers (other than those of heading 8402) and 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.