Surgeons Join Knot
Surgeons Join Knot
The fastest and easiest knot for joining two lines. The Surgeon's Join works equally well on lines of very different diameters — perfect for adding tippet to a fly leader or a fluorocarbon leader to main line.
Video by Sport Fishing Report on YouTube
About the Surgeons Join Knot
The Double Surgeon's Knot is the easiest line-to-line knot to learn and consistently tests at 95% or better of the weaker line's breaking strength. Where the Blood Knot demands equal diameters and careful technique, the Surgeon's Join is forgiving and can be tied in seconds.
It's the workhorse knot for fly fishermen building leaders and adding tippet, but equally useful for any angler who needs to quickly join a fluorocarbon leader to monofilament main line.
Best Used For
Ideal applications
- ✓ Joining any two lines
- ✓ Tippet to leader — fly fishing
- ✓ Fluorocarbon leader to mono main
- ✓ Different diameter connections
- ✓ Quick field repairs
Not ideal for
- ✗ Very heavy trolling line — use Bristol
- ✗ When a slim streamlined knot is required
Step-by-Step Instructions
Follow these 5 steps to tie the Surgeons Join Knot. Watch the video above while following along.
Step 1: Overlap the two lines
Lay both lines side by side with 6 inches of overlap, both pointing in the same direction. Hold the overlap section between your fingers.
Step 2: Form a loop with both lines
Bend both lines together to form a large loop. Treat both lines as a single unit for this step — keep them parallel.
Step 3: Pass both tag ends through twice
Pass both tag ends through the loop — then pass them through again. Two passes creates the Double Surgeon's Knot which is significantly stronger than one pass.
Step 4: Wet and pull all four strands
Wet the knot. Hold all four strands — both standing lines and both tag ends — and pull all of them simultaneously to tighten evenly.
Step 5: Trim both tag ends
Once fully seated, trim both tag ends to about 1/4 inch. Leaving a little more tag than usual prevents slipping on fluorocarbon.
Pro Tips
- Pull all four strands simultaneously to tighten evenly
- Two passes through the loop is what makes it a Double Surgeon's
- Works great for diameters up to 4x different
- Fastest line-to-line knot to tie in the field
Common Mistakes
- Only passing through once — must be twice for Double Surgeon's
- Pulling only two of the four strands to tighten
- Not wetting before tightening