The best folding fillet knife for most anglers: a flexible 6.5-inch blade that folds to 7.5 inches for a tackle bag or backpack, for under $30.
Buy it if: Kayak, backpacking and travel anglers, and anyone who wants a full-size fillet knife that packs small.
Skip it if: Anglers who mainly clean big salmon or saltwater fish, or who prefer the easier cleaning of a fixed blade.
Most fillet knives are fixed blades, which are awkward to pack. KastKing's folding fillet knife solves that: it's 13.5 inches long when open but folds down to 7.5 inches, so a full-size fillet knife fits in a tackle box, backpack or kayak hatch. Press the release to fold it.
The 6.5-inch blade is G4116 German stainless steel with a titanium-bonded, non-stick finish that KastKing says improves corrosion resistance, so it's suitable for fresh and saltwater. The handle frame is glass-reinforced polypropylene covered in grippy TPE rubber, and it comes in bright orange (easy to spot if you drop it) or black. A lightweight sheath with a belt loop is included.
On Amazon, buyers most often praise how sharp it is out of the box, the compact folding design, the comfortable textured handle and how sturdy it feels when open; several say it feels like a fixed blade. They also like the flex and the value. A few received a knife that needed sharpening first.
Any folding knife has a hinge that collects slime and fish scales, so rinse it open and let it dry fully before folding it away. If you clean fish at home or on a boat with storage space, a fixed blade is simpler; if space is tight, this is the one to get.
Here’s where its 6.5-inch blade sits against typical fish sizes. See blade length by fish for more.
This review is based on the manufacturer’s specifications, the Amazon listing and patterns in verified buyer feedback, compared against the other knives we cover. We haven’t lab-tested it. Read our method.