7 Useful Knots to Know for Fly Fishing
Updated: Jun 17, 2022
Do you feel that one of the most frustrating parts to fly fishing is the knot tying? Are you someone that may be stubborn to change flies because it is a struggle to tie a new one on? Then this article is for you. In fly fishing, we are constantly tying on new flies, adding tippet, creating two fly rigs, so on and so on. There are a lot of knots out there and you may discover one knot, try it out, love it then hate it, then find another one and repeat the process. Well, the best tip to all of that mayhem is to select a few knots, learn them, practice them, get used to tying them on the water, stick with them, and then venture out to learn a couple more knots.
Yes, some knots are stronger than others and you may hear claims from anglers that talk about the tensile strength of knots. However, there are innumerable variables at play: the size of the tippet, the temperature, the hook size, the brand of material, the tippet or monofilament material, the method to tie a certain knot, etc. You may even be swayed by someone's rhetoric to use a new type of knot, but laboratory results don't mean diddly when you cannot effectively or efficiently tie it while on the water.
So, rather than getting bogged down and worried about the strength of knots, you should focus more on correctly and efficiently tying your knots. Over time you will gravitate towards and prefer certain knots over others based on the situation, and that comes with practice, experience, lost fish, broken tippet, and everything in-between.
Below is a list of knots that I prefer to use for freshwater applications, and there are plenty of arguments for and against them. Yet, the list below is meant to provide some guidance and cut through the frustration of knot tying in order to get you back to fishing on the water rather than standing on the bank cursing at a piece of tippet. These knots all have a specific application for fly fishing and I will cover each one in detail along with the advantages and disadvantages.
Before we go through the list, the one thing I really want to impart on you is to practice these knots at home. Grab an old spool of tippet (preferably some larger diameter tippet or monofilament) and practice tying these knots. Do yourself this favor and practice, because it sucks to waste time on the water.
Yes, the clinch knot is probably the first knot you may have learned when starting fly fishing, and there's a reason for that. It is simple to tie, can be relatively strong, has several applications, and when tied well it doesn't waste a lot of tippet. If you are new to tying knots, I would recommend practicing the clinch knot first before moving on to more difficulty knots.
Video: How to Tie a Clinch Knot
The clinch knot is a great knot to use for fly sizes 12 and smaller when using tippet in the 4-7x range. It is also an effective knot to use when tying a nymph to a dry fly in order to set up a dry-dropper rig. Also, the clinch knot is useful to tie tippet to a tippet ring if you are using one of those.
Now there are situations when the clinch knot will just let you down. First, the clinch knot has a tendency to slip and come undone. I have also noticed that after fighting some larger fish or after hooking couple snags (but getting the fly back) the knot may have already begun to slip. So, after hooking into a few fish or snags, it is best to clip off and tie on a new clinch knot.
Next, and this is more of an application when tightline nymphing, it is not the best knot when tying small tippet (4, 5, 6x) to a fly that has a larger diameter hook eye (think hook sizes 10, 8, 6 and larger) as the knot will more easily come apart. The clinch knot can also be a bulky knot, so when using small delicate dry flies you may want to use a knot that has a more slender profile (we'll discuss some alternative knots below).
Here are some tips when using the clinch knot:
When tying the clinch knot with smaller diameter tippet (5, 6, or 7x) add more wraps around the standing line (i.e. 5, 6, or even 7 turns around the tippet before threading it back up through the loop near the hook eye). This will help to keep the knot from slipping.
After tying the knot, test it by pulling firmly on the tippet and checking to make sure the knot doesn't slip. At times, the knot just won't be seated correctly and it will slip and come apart, so it is better to test it rather than to lose a fish.
If you do lose a fly, bring the tippet back to you and inspect it. If it is coiled up and looks like a pig's tail then the knot wasn't tied correctly or it was tied poorly. If the tippet looks like a clean break then the tippet just snapped but the knot was tied correctly.
16-20 Knot (or Pitzen Knot)
The 16-20 knot takes its name from a fishing club called the 16-20 Club where anglers were challenged to catch a 20lb Atlantic salmon on a size 16 hook or smaller. It may also be referred to as the Pitzen knot. Compared to the clinch knot (in my own observations) this is a much stronger knot, it doesn't slip, and has a wider range of utility.
The 16-20 knot is actually a slip knot wherein the knot is tied and then slid down to rest against the hook eye. There is a huge benefit to this in that it allows you tie small tippet (such as 6x) to larger diameter hook eyes (like a size 10 hook) which is why I prefer to exclusively use this knot when tightline nymphing where I am forced at times to use larger flies on fine tippet. Beyond its strength, the 16-20 has a slender profile which is ideal for small dry flies.
There are a couple downsides to the 16-20. First, it is a difficult knot to master as you pretty much need three hands to tie it efficiently. This is a big step up from the clinch knot in difficulty, so it is best to practice this knot again and again in the comforts of your own home before trying to use it on the water. Below are two videos with two different methods to tying this knot:
Video: Tying the 16-20 Knot
Second, the 16-20 is best used with tippet 3x or smaller. Anything larger and it just does not seat correctly. However, when I am getting into those larger tippet sizes I am probably streamer fishing or using bass flies so I will gravitate towards the non slip loop knot or trilene knot. The 16-20 also eats up more tippet than compared to the clinch knot or Davy knot, but over time and with practice you can reduce the amount of wasted tippet by more efficiently tying it.
Tips for tying the 16-20 knot:
When seating the knot against the hook eye you should most often feel or hear a click or pop coming from the knot. This is an indication that the knot was seated correctly. The second indication is that the tag end will be coming out of the knot pointing parallel to the standing line.
Non Slip Loop Knot
The non slip loop knot is another strong knot (again, based on my own personal observations). You may often see this knot associated with streamer fishing. Besides it strength, the knot forms a loop in front of the hook eye which allows greater movement for the fly. When you want to maximize the amount of movement a streamer has in the water, this is a great knot to use.
The non slip loop knot is also great to use with larger diameter tippet material (3x and larger) as well as small diameter tippet. It can be a tricky knot to learn but it comes more easily than the 16-20 knot. I prefer to use it mainly for streamer fishing because I want that range of motion and strength when I target larger trout and bass.
Tying the knot does eat up a lot of tippet material which is a downside. Another disadvantage is that if you tie the knot with too large of a loop then the fly will have too great of mobility and can swing around and fowl up in the leader.
Tips for tying the non slip loop knot:
Aim to have the loop about the size or double the size of the hook eye, any larger and the fly can move too freely and fowl up around the leader.
To help make the loop small, bring the overhead knot close to the hook eye and keep it near it when tightening up the knot.
I like to use my hemostats to hold onto the tag end to help tighten and secure the knot at the end.
Triple Surgeon's Knot
This my preferred knot to use when joining a length of tippet to the leader. At a certain point, the leader becomes too short (or you have cut back into a thicker part of the leader) and you need to add tippet. The triple surgeon's knot is relatively easy to tie, it is great to join two dissimilar sized diameters of tippet together (like 4x to 2x), and it is can be used to tie fluorocarbon tippet to nylon tippet. Fluorocarbon tippet is a tough material to tie to nylon since it has a tendency to slip through the nylon, but the triple surgeon's knot is one of the better ways to splice these two materials together.
Another big benefit to the knot is that you can use one of the tag ends to attach a dropper (like a dry fly or nymph).
The one thing with adding a dropper fly is that after you tie the knot you will end up with two tag ends, and the tag end that is pointing down towards the terminal end of the leader is the one you tie the dropper to. If you tie a fly onto the tag end that is pointing back up towards the butt-end of the leader then the knot will come undone when a fish grabs the fly and pulls on it. So, the tag that is pointing back up towards the butt-end of the leader is the one you want to clip off when creating a dropper rig. This is also a great knot to use in drop shot rigs.
When I start to get into larger diameter tippet or monofilament, the triple surgeon's knot just becomes too bulky and kinks way too much. In this instance, I will most often use a blood knot (which we'll cover next).
Tips for tying the triple surgeon's knot:
Give yourself plenty of tippet and leader material to work with and make a loop that is at least the size of a quarter. This will help you to pass the leader and tippet through the loop more easily and efficiently.
Really lubricate this knot with spit or water and then close the loop down smoothly to compress it before giving it a nice quick, securing pull to lock it in place.
Make sure you hold onto all four strands when compressing the knot. Then pull on the terminal end and the original leader/standing end.
Below are a few other knots that are great to know for fly fishing. I use primarily use them for more specific applications, but you might find them useful as well.
I primarily use the blood when I need to tie larger diameter tippet or monofilament to the leader (think 2x and larger). This knot is the main knot I also use when building my own leaders (yes, you can create your own leaders...we'll write a post about that later on). The blood knot is more streamlined and symmetrical than the triple surgeon's knot and does not kink or off-angle the line as much. However, the blood knot is best used to tie similar diameter tippet together (no more than .002 in difference), and it doesn't hold as well as the triple surgeon's knot when tying fluorocarbon and nylon together.
Video: Tying the Blood Knot
The blood knot is a little tougher to tie than the triple surgeon's knot but comes quickly with just a little bit of practice. The one thing that I do see anglers using the blood knot for that I would recommend against is attaching a dropper to one of the tag ends. When you finish tying the knot, you are left with two tag ends (just like with the triple surgeon's knot) but these tag ends shoot out perpendicular to the knot. If you tie a fly onto on the of the tag ends, the fly is held straight out and will have an unnatural drift in/on the water.
This is a knot that really only use when I need to add a dropper fly to my leader. If I was using the tag end of a triple surgeon's knot to attach a fly to there comes a point when the tag end becomes too short (after multiple fly changes). To create a new tag end, I will tie a uni knot (with about 10 inches of tippet material) above the original triple surgeon's knot and then slide it down until it rests against the original triple surgeon's knot. Then, I will trim the tag end until it is about 6-8 inches in length (any longer than this and the tag end and fly will wrap around the leader a lot). From there, attach your fly and you should be good to go for about 5-8 more fly changes.
The perfection loop is on any leader you buy from a fly shop, if there isn't a perfection at the end of the leader then you'll need to tie one in order to loop and connect the leader to the end of the fly (if you are using the welded loop on you fly line to do so).
Video: Tying the Perfection Loop
Final Tips for Tying Fly Fishing Knots
Always test the knot after tying. The knot may slip or snap too easily, but it is best to have this happen before a fish takes and breaks off a fly. As you tie more and more knots, with different diameters of tippet, you will also get a feel for when a knot is tied correctly.
Lubricate the knot with spit, water, chapstick, etc. before fully cinching down the knot. There is a lot of heat and friction that is created when tightening down the knot and a little bit of spit or water will help to keep the tippet material from heating up too much and causing material failure.
Before tying a knot, inspect the tippet material. Tippet material will get beat up if you are fishing over boulders or logs which rub against and weaken the line. Feel the tippet with your fingers for any abrasive spots, if you find any then clip it off above the abrasive area. Tippet also expires (nylon expires more quickly than fluorocarbon) so write down the date of purchase and buy a new spool after about 2 years. Read: Does Tippet Expire? and An In-Depth Guide to Tippet.
Get comfortable tying knots, don't try and do it hunched over or in an awkward position. Tie with relaxed shoulders and with the material up close to your chest.
Other Knots to Check Out
Orvis Knot- Great to use with small and larger tippet sizes, and better strength than a clinch knot (in my opinion). It can be finicky to finish tying the knot and will take practice.
Davy Knot- This knot has a much smaller profile than the clinch knot, but is not as strong as a 16-20 knot (again, in my own opinion) and it can slip just like the clinch knot. It also it a bit easier to tie than the Orvis knot and won't eat up a lot of tippet material.
Trilene Knot- This knot is just a clinch knot that is passed through the hook eye twice rather than just once, which makes it a stronger knot than the clinch knot. It is a good knot to use with heavier tippet (2x and larger) and I like to use this knot for large bass top water flies when I don't need the freedom of movement of a non slip loop knot.
As always, if you are interested in booking a guided fly fishing trip with us Contact Us, or check out our Spokane River Guided Trips page for more information. We also offer Fly Fishing Instructional Lessons here in Spokane if you are interested in spending just a couple hours out on the water improving your fly fishing skills.