Water retting produces a cleaner, more uniform fiber suited to fine linen yarn and apparel fabrics, but is increasingly restricted due to water-pollution concerns. Dew retting is more common and environmentally acceptable, yielding a coarser fiber better suited to industrial textiles, technical fabrics, and composite reinforcement. Buyers should specify retting method in purchase contracts to ensure fiber compatibility with their spinning or processing equipment.

Once flax undergoes mechanical operations — breaking, scutching, or hackling — it exits the raw/retted category and is classified as processed-but-not-spun flax. Importers should confirm with suppliers exactly which operations have been performed at origin, as even partial mechanical processing can shift the applicable classification.