Sewing Thread of Synthetic Staple Fibers

Sewing thread spun from staple fibers (short, discrete fiber lengths) falls under heading 5508, while thread made from continuous filament yarn is classified under heading 5401. The distinction is based on the yarn construction method: staple-spun thread has a characteristic hairiness and texture, whereas filament thread is smoother. Importers should confirm the yarn construction type with the manufacturer to ensure correct classification.

Under HTS 5508100000, the duty rate is the same regardless of whether the thread is on industrial cones or retail spools. However, retail packaging may trigger additional labeling requirements under the Textile Fiber Products Identification Act, which requires fiber content, country of origin, and manufacturer identification on consumer-facing packaging. Industrial shipments on large cones are generally exempt from retail labeling rules.