Haddock and Atlantic cod are close cousins from the cod family, yet in the crate and on the plate they are two different fish. Here is how to tell them apart — whole and as fillets.
Haddock (Melanogrammus aeglefinus) and Atlantic cod (Gadus morhua) belong to the same cod family, swim in the same cold waters of the North Atlantic and look alike at first glance: three dorsal fins, two anal fins, a slender profile. They are sometimes confused in trade — and the difference concerns looks, meat and price alike. Here is how to tell them apart every time.
The quickest test: the blotch and the lateral line
Two features identify a haddock within seconds. The first is the dark oval blotch above the pectoral fin — the famous “thumbprint”. The second is the lateral line: black and almost straight on a haddock, pale creamy-white and clearly arched over the pectoral fin on a cod. Cod has no shoulder blotch; instead, its back and flanks carry a mottled, olive-brown pattern.
Other differences in build
- Chin barbel — long and prominent on cod, short and barely visible on haddock.
- First dorsal fin — tall and pointed on haddock, lower and rounded on cod.
- Mouth — haddock has a smaller, underslung mouth (it feeds near the bottom); cod has a large mouth with a protruding upper jaw.
- Colouring — haddock is silvery grey with a darker back; cod is speckled, from olive to brown depending on the fishing ground.
- Size — cod grows considerably larger; a typical market haddock is smaller and slimmer.
Telling them apart as fillets
Without the head and skin it gets harder, but differences remain. A cod fillet is thicker, with large distinct flakes and a snow-white colour once cooked. A haddock fillet is thinner and more delicate, with a finer texture and a slightly sweeter taste; the raw flesh can look a touch more translucent. The skin, if left on, is another clue: the dark lateral line and the blotch point unmistakably to haddock — which is why haddock fillets are traditionally sold skin-on in the UK.
Which one for the kitchen?
It is not a question of better or worse, but of what for. Cod gives thick, meaty portions with a neutral flavour — ideal for baking, frying and classic white-fish dishes. Haddock, more delicate and sweeter, is the favourite of British fish & chips and the basis of smoked specialities such as Scottish finnan haddie. In wholesale both species are treated as premium fish from the same grounds of the North Atlantic and the Barents Sea.
Nova Seafood offers both Atlantic cod and haddock — IQF-frozen, with full traceability of the fishing ground. Contact us for specifications and current availability.
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