What is a Uni to Uni Knot?

The uni to uni knot, otherwise known as the double uni, is used to connect your fishing leader to the main line. This comes into play if you do not want to use a barrel swivel.

It is very popular among saltwater fisherman, but can be utilized in freshwater as well.

This is a great knot to use because the connection between your leader and main line must be very strong so that you don’t lose the fish.

For saltwater, you might be connecting braid to a steel leader so that you have the ability to catch fish with teeth. The steel leader will prevent them from biting through the line.

This knot has a high breaking strength and is quick and easy to tie. It can also be used to connect many different types of line together of varying size. An issue you’ll find is that it can be quite bulky, but trimming the excess line close to the knot can help with this.

Of all connecting knots, the uni to uni might be one of the most popular among anglers. This is because of strength, durability, and how easy it is to tie.

How to Tie the Uni to Uni Knot

  1. Lay the lines next to each other and form in a loop in one of them.
  2. Make five to seven turns through the loop and around both of the lines.
  3. Pull the tag end and the running line to tighten the loop. Do not over tighten.
  4. Make a loop in the other line and make five turns then tighten. Do not over tighten.
  5. Pull on both lines to slide the two tight together.
  6. Give a firm pull on both lines to make sure the loops and tight and the knot is secure.
  7. Trim the excess line so that it does not get hung up on the guides of your rod.

Uni to Uni Knot Vs. Other Knots

The uni to uni is a very strong knot that can hold up to most large fish. However it is not regarded as the strongest connecting knot.

The FG knot is considered to be one of, if not the strongest connecting knot that you can tie and is recommended for using with large gamefish.

Even though it is more complicated and takes longer to tie, the reason the FG is regarded as being so strong is because of how slim it is compared to a uni to uni.

The smaller profile allows it slide through the guides of rod easier and results in less friction on the connection.

However, when compared to the ever popular Albright knot, the uni to uni comes out as the winner. The reason the improved Albright is not as effective, is because your main line can begin to cut into your leader. This is especially true if you are using a braid to mono connection.

Think of it this way; If you have ever tightened a braided knot with your hand and received a cut, the same thing happens with the mono line.

It will cut in and over time the mono will break and will result in a lost fish.

With the uni to uni, you’ll see that the two knots will tighten against each other instead of cutting into the leader. This allows the knot to work to its full strength without cutting into the line.

Uni to Uni Knot Variations

The variation to a uni to uni is called the double double uni knot. This is a strong knot that does not break easily, is quick to tie and does not slip on your line.

It works best when joining braid to a fluorocarbon leader. This knot is tied the exact same way a uni to uni is done except you double over the main line before you begin the tying process.

Be aware that if using this knot you could potentially overstretch the monofilament if connected to braid.

Uni to Uni knot Alternatives

FG knot

As stated earlier, the FG knot is the strongest connecting knot that you can use. Its slim appearance allows it to slide through the guides on your rod without issue. It also has the highest breaking strength of any connecting knot as well.

Here’s how to tie it:

  1. Wrap your leader around your main line for a total of 20 times. Alternate the wrapping by going towards your rod then wrapping towards you.
  2. Once you have all the wraps complete, hold the coils with one of your free hands and tie two hitch knots to lock the coils into place.
  3. Apply heavy tension by pulling on the main line as well as the leader to tighten down
  4. Cut the tag end of the line as close to the coils as possible. This extra line will not budge so don’t be shy to cut very close.
  5. Tie two more hitch knots above the end of the leader and tighten to fully lock the knot into place. This will form a smooth end at the top.
  6. Cut off the tag end of your main line.

If this knot sounds too labor intensive, you could also choose to tie the improved Albright. As mentioned earlier, if you’re using lighter braid on your main line and lighter monofilament on your leader then the main line could begin to cut into your leader.

The Albright works best when using a steel leader or heavy thick monofilament.

  1. Gather your main line and form a loop so the main line now runs parallel with itself.
  2. Take your leader and run it through the loop in your main line.
  3. Wrap the leader around the main lines 10 times.
  4. Bring the leader back through the main line loop and wrap the leader around the top of the loop, as well as the leader 5 times.
  5. Grab the tag end of your leader and the main line and pull to tighten the knot.
  6. Trim off excess line.


Connecting knots can seem time consuming and tricky at first, but are a mainstay if you want to be a successful angler.

Using heavier line attached to your reel while attaching a near invisible fluorocarbon or a strong steel leader can result in not only you catching a lot of fish, but a lot of big fish.