Fish Cooking Temperature: Safe Internal Temps by Species

The FSA does not prescribe a single mandatory cooking temperature for fish, but 63C core temperature is the widely accepted standard for most fin fish species. At 63C, the fish flesh is opaque and flakes easily, and pathogenic bacteria are destroyed. Some food safety guides recommend 70C for 2 minutes as an equivalent, and this provides a larger safety margin. For white fish (cod, haddock, plaice, sea bass, bream), 63C is appropriate. The flesh should be opaque and firm but not dry. For oily fish (salmon, mackerel, trout), 63C is also the standard. Salmon can be safely served at lower temperatures in specific controlled circumstances (similar to rare beef), but this requires documented HACCP controls. For shellfish (prawns, mussels, clams, oysters, crab, lobster), the recommendation is 75C. Shellfish carry a higher risk of norovirus and Vibrio bacteria, and the higher temperature provides the necessary kill step. Prawns turn pink and opaque when cooked; mussels and clams should open during cooking, and any that remain closed should be discarded.

Fish fillets are typically thin, which makes probing more challenging than with meat. Insert the probe horizontally into the thickest part of the fillet, aiming for the geometric centre. For a thick fillet such as cod loin, the probe can be inserted from the side. For thinner fillets, you may need to fold the fillet or stack two together to get the probe deep enough for an accurate reading. For batch-cooked fish (such as fish and chips), probe at least 2-3 pieces per batch, selecting the thickest items. The batter or breadcrumb coating insulates the fish and can give a misleading surface reading, so always probe through to the centre of the fish itself. For whole fish, probe the thickest part behind the head, inserting the probe at an angle to reach the flesh near the backbone. This is the last area to reach temperature in a whole fish.