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

Every line of heading 6903

• 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.
• 6903.10.00.00 Containing by weight more than 50 percent of free carbon (kg): General Free; Special none; Column 2 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) (kg): General Free; Special none; Column 2 30%.
• 6903.90.00 Other (under: 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): General Free; Special none; Column 2 30%.
• 6903.90.00.10 Of clay (under: Other) (kg).
• 6903.90.00.50 Other (under: Other) (kg).

From MFG Calcs data: Technical and refractory ceramics

U.S. imports of technical and refractory ceramics (headings 6903, 6909) came to $1.29B in 2025, with $129M in calculated duty: an effective duty of 10.0%, every duty included.

Effective duty in Sep 2026: 11.1%, against 13.7% in Sep 2025.

Largest sources in 2025: Japan $408M at 8.7% effective duty; Mexico $309M at 0.1% effective duty; Germany $114M at 10.5% effective duty; China $98.3M at 45.8% effective duty; Poland $52.3M at 10.4% effective duty.

These are family totals from U.S. import statistics published through USITC DataWeb, not this heading's rate alone; effective duty is calculated duty as a share of customs value, an estimate, not a ruling.

• Technical and refractory ceramics: tariffs and imports
• Technical and refractory ceramics: landed cost by country
• Technical and refractory ceramics: reshoring outlook

About these rates

The rates are those printed in the 2026 HTS Revision 23, published by the U.S. International Trade Commission. A 10-digit statistical line takes the rates printed on the 8-digit line above it. Chapter 99 duties (Section 232, Section 301, IEEPA) depend on the product, the origin and the date, are charged on top, and are not included. A code here is a strong lead, not a ruling: confirm it with a customs broker or a CBP binding ruling.