Fly Fishing Knots - Part 1: Blood Knot


Fly fishing without knots? Not possible! Whether for mounting the fly, for connecting the leader and tippet, as transition between flying line and leader or for securing the backing ... without knots it just doesn't work. In our series "Knots for Fly Fishers" we introduce you to an important knot in each video and explain the most important applications in practice.


The Blood Knot

The Blood Knot is one of the strongest knot for connecting two ends of a line - for example two pieces of monofilament. In addition to its strength, another advantage of the Blood Knot is that it enables a straight-line connection. The two ends of the line merge almost seamlessly into each other. With other knots, however, an angle is created which, depending on the intended use, can have a negative influence on your presentation. Because the Blood Knot is very thin, it passes through the rod rings without any problems, so you don't have to worry about this when fighting or landing a fish. Ideally, two line ends are connected with the blood knot, whose diameters do not differ too much from each other. As a rule of thumb, the thinner the line ends, the more turns are needed (e.g. 5-7 turns for thin trout leaders) and the thicker the line ends, the fewer turns you need to make the knot.


Blood Knot in practice

In practice, the blood knot is used by us fly fishermen to:

  • connect a tapered leader with a tippet. Especially when fishing fine dry flies, the blood knot is a more delicate connection between leader and tippet than a Pitzenbauer ring (tippet ring).
  • produce your own tapered leaders. Even though there are a number of very good tapered leaders on the market, some fly fishers still rely on self-knotted tapered leaders when fishing for Trout and Grayling. By combining different diameters and lengths, the characteristics of the leader can be individually determined. Also in saltwater fishing the blood knot is often used to make individual leaders - for example when fishing for Tarpon.
  • create a side arm (dropper). The result of a blood knot are two line ends, each of which protrude at a 90 degree angle from the rest of the leader. One of these side arms can be used to attach a fly. Similar to a surgeon's knot, the side arm can be used to knot a dry fly (in a dropper-hopper rig) or a nymph (when fishing with two nymphs; dropper nymphj). Even in the Sea Trout fishery a dropper setup with a blood knot is not atypical.


The blood knot is used for Trout fishing, Salmon fishing, Sea Trout fishing and also in tropical saltwater. It is an indispensable knot that has been used since it was first mentioned in fishing literature at the beginning of the 20th century. As with any other knot, it is advisable to dispute the ends of the line before tightening the blood knot.

Happy knotting and tight lines on the water!