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How to Tie the Surgeon’s Knot

The surgeon’s knot is one of the best knots for joining two lines together.

Because it works well with very thin lines, it’s popular among anglers for joining two fishing lines together.

Better yet, it’s just as effective at joining two lines of different sizes as it is at joining two lines of similar sizes. It’s a great knot for fluorocarbon, monofilament, and braided lines.

Yet another reason why the surgeon’s knot is so popular for fishing is because of just how easy it is to tie. It’s a quick, simple fishing knot you can tie in just seconds – almost without thinking.

Today, I’m going to show you exactly how to tie the surgeon’s knot in step-by-step detail.

How to Tie a Surgeon’s Knot

The surgeon’s knot is easy to tie with just a few quick steps. To better illustrate the process, we’ll use thicker lines, although you’ll most likely be using fishing line.

Step 1

Overlap two lines by several inches for Surgeon's Knot

Overlap the two lines by several inches.

Step 2

Form a loop to tie Surgeon's Knot

Form a loop with the overlapping sections of line. Keep the loop loose for now.

Step 3

Wrap free end around loop two times to form Surgeon's Knot

Wrap the overlapping end with the shorter line (usually the tippet or leader) and the tag end of the other line through the loop two lines.

Step 4

Pull lines tight to form Surgeon's Knot

Pull at the ends of the lines in opposite directions to tighten the knot. Cut the loose tag ends of each line once tight.

Tips on Tying the Surgeon’s Knot

Remember to treat the overlapping portions of the lines as a single line.

After you overlap the two lines in step one, adding a bit of saliva to the lines will help them stick together and act like a single line.

This is extremely helpful not only for step 2 (forming a loop), but especially for step 3 (wrapping the line through the loop twice).

To add more strength, it’s often better to double up on step 3. Rather than just wrapping the line through the loop once or twice, we recommend doing so three or four times if not up to as many as six times for added holding strength.

Once the knot is secure, trim the loose ends. Try to do this as close to the fishing line as possible for a smoother knot. I like to use nail clippers to trim excess fishing line.

For a more in-depth tutorial and additional information on the Surgeon’s knot, check out our video!

Best Uses for the Surgeon’s Knot

Surgeon's Knot

As its name implies, the surgeon’s knot is popularly used by surgeons when maintaining proper tension on a suture is important.

However, this knot is most commonly used for fishing. It’s a quick, simple, and effective knot for joining two lines together.

After you learn how to tie the surgeon’s knot, you’ll see just how easy it is. This is a great fishing knot to tie in low light conditions, when your hands are cold and wet, or when you need to tie a knot very quickly – such as after receiving a hot bite.

The surgeon’s knot also works well with slightly larger line than fishing line, such as twine. In fact, it’s sometimes used by butchers to hold raw meat together with twine.

Another less common, but just as beneficial use, of the surgeon’s knot is for tying quilts.

Pros and Cons of the Surgeon’s Knot

Despite how effective it is for joining lines of similar and differing lengths together, the surgeon’s knot has its own set of pros and cons when it comes to using it for fishing.

Surgeon’s Knot Advantages

Here are the main benefits of the surgeon’s knot:

  • Quick – This knot takes just seconds to tie which is great for when the fish are biting!
  • Versatile – The knot can be used just as effectively on lines of similar and differing diameters, including two slick monofilament lines, without slipping.
  • Fly Fishing – The surgeon’s knot is hands down one of the best knots for fly fishing as it allows you to quickly attach your tippet to your fishing line.

Surgeon’s Knot Disadvantages

Here are the main drawbacks of the surgeon’s knot:

  • Bulky – This is far from the cleanest knot. It can get quite bulky, especially if you double up on the number of wrap throughs.

History of the Surgeon’s Knot

Person Reeling in a Fish

The surgeon’s knot was originally developed to hold sutures tight during surgery.

Because of the similarities between the two tasks, the knot was soon adapted for use holding raw meat together with butcher’s twine by butchers.

The surgeon’s knot has long been popular among anglers, although it has wavered in and out of favor in the fishing world over the years.

This fishing knot is especially popular for flying fishing for those that want to build their own tapered leaders.

Although once used mostly by freshwater anglers only, the surgeon’s knot is now in popular use for saltwater fishing as well.

Variations of the Surgeon’s Knot

The surgeon’s knot was originally adapted from the reef knot.

It basically adds an extra twist onto the reef knot (also known as a square knot) to add more holding strength to the finished knot.

The main variation of the surgeon’s knot is the double surgeon’s knot which simply adds another loop to the knot. Add yet another loop for the triple surgeon’s knot.

When it comes to attaching a leader to the main line for fishing, the surgeon’s knot is almost always doubled up in its normal form – which, technically, makes it a double surgeon’s knot.

Although the surgeon’s knot is a highly effective fishing knot, especially when time is of the essence (such as after a hot bite), the blood knot is a close relative that’s notably “cleaner” than the surgeon’s knot while accomplishing much the same task.

The blood knot is also better for very thin monofilament lines.

Learn to Tie Other Fishing Knots!

The surgeon’s knot is one of those knots that every angler should learn.

Not only is it quick and simple today, but it’s very versatile thanks to its ability to connect two fishing lines of different or similar lengths.

But the surgeon’s knot is far from the only fishing knot worth knowing.

To learn how to tie other useful fishing knots, check out our guide to the best fishing knots to learn more about the 10 best knots for fishing.

Still can’t find the knot you’re looking for?

Then chances are you’ll find it on our complete list of survival knots!