0303.64.00.00 - Haddock (Melanogrammus aeglefinus)

This HTS category specifically covers frozen haddock, scientifically identified as *Melanogrammus aeglefinus*. Within Chapter 3 of the Harmonized Tariff Schedule, this subheading falls under the broader classification of frozen fish, excluding fillets and other fish meat of heading 0304. It is further refined to include fish from specific families, including the Gadidae family, to which haddock belongs.

Distinguishing this category from its siblings, it is crucial to identify the species. For instance, sibling subheading 0303.63.00 covers various species of cod, while 0303.65.00.00 is dedicated to coalfish. This subheading is solely for haddock, differentiating it from other members of the Gadidae family and other fish types listed at the same level. The classification hinges on the precise species of the frozen fish, ensuring accurate customs declaration.

As a leaf node, this subheading does not have further subdivisions. Therefore, classification under 0303.64.00.00 is definitive for frozen haddock. It is important for importers and exporters to confirm the species of the frozen fish through accompanying documentation or by physical inspection if necessary, to ensure correct entry and compliance with customs regulations.