Other refractory ceramic goods — HTS 6903
Other refractory ceramic goods (for example, retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and slide gates), other than those of siliceous fossil meals or of similar siliceous earths
Chapter 69 › Heading 6903
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 6903 is a broad product category for certain refractory ceramic goods—heat-resistant ceramic articles used in furnaces, kilns, foundries, and industrial heating processes. Examples include retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods, and slide gates. The heading does not cover comparable goods made from siliceous fossil meals or similar siliceous earths, which are handled elsewhere in the tariff.
To reach the correct 8-digit HTS code, start with heading 6903 and read the more detailed subheadings and statistical provisions beneath it. The classification commonly turns on the article’s material or composition and its specific type or design. Confirm the product’s ceramic composition, physical form, dimensions or construction where relevant, and intended industrial function; the final code must match the complete tariff description, not just the product’s marketing name.
What to check
- Obtain the manufacturer’s technical datasheet, including ceramic composition, refractory characteristics, and manufacturing method.
- Identify the article’s specific form and function—for example, crucible, tube, nozzle, support, or another listed refractory good.
- Check whether the product is made from siliceous fossil meal or a similar siliceous earth, because that may place it outside heading 6903.
- Read every applicable 6-, 8-, and statistical-level description under heading 6903; do not stop at the heading title.
- Compare the proposed classification with binding rulings, official classification guidance, or a licensed customs broker when the material or function is unclear.
HTS heading 6903 summary
Other refractory ceramic goods is a 4-digit product category containing 3 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 |
|---|---|---|---|---|
| 6903.10.00.00 👉 | Containing by weight more than 50 percent of free carbon | Free | — | 45% |
| 6903.20.00.00 👉 | Containing by weight more than 50 percent of alumina (Al2O3) or of a mixture or compound of alumina and of silica (SiO2) | Free | — | 30% |
| 6903.90.00 👉 | Other | Free | — | 30% |
"Special" shows the free-trade-agreement rate; open a code to see exactly which countries qualify.
Common questions
What products fall under HTS heading 6903?
Other refractory ceramic goods (for example, retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and slide gates), other than those of siliceous fossil meals or of similar siliceous earths. 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.