Defrosting Fish

There are so many high quality frozen uncooked fish products that you can buy straight from the supermarket and use to prepare delicious meals, reducing your food waste and household bills.

All of our tips are for using fish that has been commercially frozen– this is uncooked fish that has been frozen by the manufacturer, ensuring it is of the highest quality and can be cooked safely from frozen.

Make sure never to defrost fish at room temperature or in warm or hot water as this is when bacteria can multiply rapidly.

A quicker and well-known way of defrosting fish is in cold water. The fish must be in a sealed bag for safety and to preserve the flavour, and submerged in water until it is defrosted.

Defrosting fish

Option one – in the fridge

  1. Do not remove fish from packaging
  2. Place fish in a bowl
  3. Place bowl at the bottom of the fridge
  4. Leave until fully defrosted. Defrost time is typically six to eight hours per lb.

Option two – in the microwave

  1. Always refer to microwave instructions
  2. Place on microwave rack in a microwave proof bowl or plate
  3. Microwave for half the allotted time
  4. Turn over the fish and microwave for the remaining time
  5. Cook immediately.

Never defrost fish at room temperature. Never defrost fish in warm or hot water.

Defrosting fish in the fridge

  • The temperature of the refrigerator should be kept at 5°C or below, as anything above this may allow the multiplication of bacteria.
  • Keep the fish in its packaging or wrap in paper and place on a plate to catch the drips as it thaws, keep away from any ready-to-eat foods.
  • Place in a bowl at the bottom of the fridge to thaw, away from any ready-to-eat foods.
  • Leave in the fridge until fully defrosted using the time guide above.

Defrosting fish in the microwave

Defrosting fish in the microwave is the quickest method, but can be tricky to achieve an even thaw, so should be undertaken with extra care and attention.

  • Always refer to the microwave handbook and product instructions for guidance on defrosting in the microwave
  • Place the fish on a microwave rack in a microwave-safe bowl or plate to catch drips
  • Microwave for half the allotted time and then turn the fish over so that the thinnest sections of the fish are towards the middle
  • Microwave for the time remaining
  • Fish defrosted in the microwave should be cooked immediately.

Want to read more? We’ve created guides on how to defrost chicken, fishsausages, turkey and mince.