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Filleting a whole round fish

Advanced Butchery and seafood

Filleting a whole round fish is cutting the two boneless sides off a round fish like trout, bass or snapper, leaving the skeleton behind.

By Cory, founder of Pantry to Pan · Published October 20, 2026 · Updated October 22, 2026

Written with AI help from the sources listed, and published by Cory. Sources: USDA safe minimum internal temperatures, USDA on the danger zone (40-140°F). Spot a mistake? Tell us and we'll fix it.

How do you do it?

1. Scale it by scraping the back of a knife from tail to head under running water, then gut it if needed.
2. Use a flexible fillet knife. Hold the head with your hand flat. Cut behind the gill and side fin down to the backbone.
3. Turn the blade toward the tail and slide it along the backbone, keeping it pressed against the bones, until the fillet lifts off.
4. Flip and repeat, then trim off the belly bones and check for pin bones. Save the frame for stock.

Why does it work?

A round fish has one fillet each side of the spine, whereas a flatfish has four. Fish muscle is short flakes held together by thin, delicate connective tissue, so it tears easily: long, smooth strokes against the bones keep it in one piece. Fresh fish has clear eyes, red gills and firm flesh that springs back, and smells of the sea, not fishy.

What are the common mistakes?

• Angling the blade up off the bones — you leave meat on the frame.
• Short, choppy cuts — a ragged fillet that falls apart.
• A wet, slippery board — fish slides; set a damp towel underneath.

Still stuck? Watch someone do it on YouTube.

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