Heading 0304 covers raw fish fillets and minced fish, fresh, chilled, or frozen. Once fish is cooked, breaded, or combined with other ingredients in a way that constitutes preparation, it typically moves to Chapter 16 (prepared fish). The degree of processing and whether the fish remains the essential character of the product are the deciding factors.

Antidumping and countervailing duty orders cover shrimp from several countries and certain fish species from specific origins. These orders are line- and country-specific, so importers should check the Commerce Department's active order list against the precise HTS subheading and country of origin before entry.