HTS Chapters 61 and 62 separate knit and woven garments into entirely different classification trees with different duty rates and, historically, different quota treatment. Misidentifying a garment's fabric construction — for example, calling a knit fabric woven — is one of the most common apparel classification errors and can result in duty underpayment and CBP penalties.

Apparel rules of origin under US free trade agreements typically require 'yarn-forward' or 'fabric-forward' construction, meaning the fabric or yarn must originate in the FTA partner country for the garment to qualify for preferential duty rates. Goods that do not meet these rules are assessed at the standard column 1 rate, which for many apparel categories remains among the highest in the US tariff schedule.