The Best Fish Fillet Knives

Blade length by fish size

Length is the first decision, and it follows the fish. A blade that is too short saws back and forth through a large fillet; one that is too long is clumsy on a sardine or a small trout. As a rule of thumb, the blade should be a little longer than the fillet is wide, so one long, smooth stroke lifts it from the bones.

If you buy one knife, 7 inches covers the fish most coastal cooks bring home: bream, bass, mackerel and snapper. Add an 8-inch blade if salmon is a regular on your table, and think about an electric knife only if you clean fish by the cooler-load.

Flexible or firm?

Flex lets the blade ride over the backbone and around the rib cage, so less flesh stays on the frame. Too much flex, though, and the tip wanders in a thick salmon fillet or when you run the blade along the skin to remove it. Tapered blades, such as Bubba's, get thinner toward the tip, so they bend most where you work around bones and stay steadier near the handle. For round fish and careful rib work, choose flexible; for big, flat fillets and skinning, a little more stiffness helps. That is why the electric Bubba comes with both flex and stiff blades.

Steel and saltwater: what rusts and what doesn't

Stainless steel is stain-resistant, not stain-proof. Salt water, fish blood and a damp sheath will spot almost any blade if it is put away wet. The knives here use proven stainless steels – X50CrMoV15 at Dalstrong, Swedish 12C27 at Morakniv, 9Cr18MoV under a titanium-nitride coating at Bubba – and all of them stay bright with the same three habits: rinse in fresh water right after use, wash by hand, dry completely.

Coatings such as Bubba's titanium nitride add a barrier against rust and pitting, which helps on a boat where fresh water is scarce. Leather sheaths, like Rapala's, are handsome but hold moisture: after a fishing day, take the knife out and let both dry separately.

A handle that grips when wet

A fillet knife spends its life in slime, scales and cold water, so the handle matters more than it looks. Textured rubber, as on the Morakniv, the Victorinox Fibrox and Bubba's grip, stays secure in wet hands, and a finger guard keeps your fingers away from the edge when you push through skin. Wood and G10 feel good in a dry kitchen; on a wet deck, rubber wins.

How to keep a fillet knife sharp

• Hone lightly before each session with a honing rod or a fine ceramic; it straightens the thin edge that flexible blades roll easily.
• Sharpen when the knife starts to drag or tear the skin, not on a schedule. A whetstone or a guided sharpener gives the best edge; the single-stage sharpener that comes with the Rapala is fine for touch-ups on a trip.
• Keep the angle the maker sets – Dalstrong gives 16–18° per side for the Gladiator.
• Skip the dishwasher, even when the maker allows it (Victorinox rates the Fibrox as dishwasher-safe): heat, detergent and other cutlery dull an edge quickly.
• Store the knife in its sheath or on a magnetic strip, never loose in a drawer, and cut on wood or plastic, never on stone, glass or metal.

How we chose

We started from the job – filleting the fish people grill by the coast – and set the criteria first: blade length, flex, steel and corrosion resistance, grip when wet, and what comes in the box. Then we read the manufacturers' specifications and, where a maker's page said little, the product pages of specialist fishing retailers and the trade press. We kept a spread of price ranges and checked which knives the Amazon stores in the US, the UK and Germany sell; a knife that your country's store does not sell does not appear on your version of this page. The Morakniv was long sold as the Fishing Comfort Fillet 155; Morakniv now lists it as the Companion Fishing Fillet 155. We have not used these knives ourselves, and we earn a commission on purchases through our links; it does not change what we recommend.