Side by Side

Atlantic Cod Gadus morhua

Typical: 22–34 in, 4–15 lb

Quickest tell: A pale curved white lateral line plus a clear chin barbel and overhanging upper jaw separate cod from the dark-lined, thumbprint-marked haddock and the jutting-jawed, forked-tailed pollock.

• heavy body, color variable (greenish to reddish-brown) with many small spots
• pale, gently curved (arched) white lateral line
• prominent single chin barbel
• three dorsal fins and two anal fins
• squared-off tail; upper jaw overhangs the lower

Full Atlantic Cod guide — season, gear and rules →

Haddock Melanogrammus aeglefinus

Typical: 16–24 in, 2–5 lb

Key field mark: The dark lateral line plus the black 'devil's thumbprint' over the pectoral fin instantly separate haddock from cod (pale/white lateral line, overhanging upper jaw) and from green forked-tailed pollock.

• dark gray back, silver sides, dark (black) lateral line
• prominent black 'thumbprint' blotch above the pectoral fin
• three dorsal fins, the first tall and pointed
• small chin barbel present
• slightly forked-to-square tail; no overhang/spotting like cod

Full Haddock guide — season, gear and rules →

When Each Is Running July — current month highlighted

Where Atlantic Cod and Haddock Overlap

Both run in Northeast — that is where telling them apart actually matters.

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