Fluorocarbon vs Monofilament Leaders/Tippet - What’s the Difference?

There is a fair amount of confusion when it comes to Fluorocarbon and Monofilament. Why are there two different materials, what is the difference between the two, and when/how does a fisherman decide to use them? There is definitely a difference between the two, and it's not just price. Most people think one of two things if they haven't compared them before, it's usually - they assume Fluoro is better because it's more expensive, OR they think it's a scam because "their grandfather caught a 60lb fish on mono and there's no need for fluoro." Both thought processes are indeed very reasonable. But, here are the main differences between Fluorocarbon and Monofilament and also, more importantly, when/how to use them.  


When it comes to comparing whether one material is "stronger" than another, there are a lot of factors to consider within leaders/tippet in fly fishing. Most of it however has to do with the manufacturer. If you look at a pack of leaders from Rio, their 3X tippet might have a different breaking strength listed than 3X from Scientific Anglers..Or one brand's 5X tippet seems wider than another brand's. This is just part of the deal- it can be confusing and present all kinds of variables. So with this article, I am going to be more concerned with what Mono or Fluoro is going to inherently provide for me. 

Fluorocarbon is significantly more durable than mono. There are a couple of reasons for this. For one, fluoro is a harder material than mono and provides a more abrasion resistant leader and tippet. This is important for situations when you're fishing nymphs along the bottom of a river, fishing on a coral flat for bonefish/permit, or swinging streamers for steelhead and salmon, or throwing deceivers off barnacle covered rocks for stripers.    

Fluorocarbon also does not absorb water or break down from the elements, including UV sun rays. Being impermeable to water, Fluoro does not weaken like mono after being continuously saturated. The fact that Fluorocarbon does not break down like Mono after a while is an important factor - especially if you are still reaching for that 4 year old spool of tippet in your sling pack...

Fluorocarbon vs Monofilament

Floating Or Sinking?

This is a consistent question I will ask myself when deciding what leader or tippet material to tie on. Monofilament is not as dense as Fluoro. This make mono more buoyant - quite a bit so actually...So, if I am about to throw some dry flies for trout, poppers for bass, or really anything on the surface I will grab the mono. On the other hand, anything sub-surface is better fished with fluorocarbon (think nymphs, streamers, wet flies). 


This is a very hotly debated factor within this conversation. If you've heard one thing about the difference(s) of Fluoro vs Mono - this seems to be the one. Most likely because a product that is "more invisible" to fish seems to be pretty alluring. And although you can do a simple test with different strands of Fluoro and mono while dipping them in water on your own, I personally do not think there is a definitive difference, visibly, in water. As a human I can see a difference in the two while in water. But I'm a human with human eyes, not a fish with fish eyes. So I think the verdict is still out on this one...but certainly something to consider. 


As mentioned earlier, fluoro is more dense than mono. This makes mono better for tying knots as the softness of mono provides better grip for the knot. Although I have not personally seen a distinct failed knot due to fluoro, I do see a very clear difference when tying knots especially in heavier tippets. If I'm making leaders for larger species like tarpon, I find mono much easier to work with.

Fly Fishing Knots

The Winner...?

Is there one? Not sure...I think it's really more situationally based than anything else. Monofiliament and Fluorocarbon are certainly different and can be individually advantageous if used properly. Fluorocarbon, although more expensive, can give the angler a better material for certain tactics - on the other hand you can be out-fished by another guy fishing mono if it's the right situation. 


Words + Photo: Josh Thelin


Josh (All Points):

Hi Frank – This is GREAT real life info and the fact you can attest to this is incredibly useful. I’m very sorry to hear about those trophy bass you lost, I hope you threw away those spools of mono afterwards!

Hi Don – This is a fantastic question! It really comes down to diameter/strength. Fly fishing (fluorocarbon) manufacturers are spending time/money/resources in developing thinner diameter fluorocarbon that is also strong(er). So that is where you will see the biggest difference – check out a spool of “conventional spinning” fluoro and then a spool of fly fishing tippet and you will see a difference in the diameter/strength. I hope that helps!

- Josh

Aug 24, 2017

Don Conley:

Good article, I like to use fluorocarbon over mono is most situations. Most of my fly fishing is in the salt, SW Fla and NE Stripers. I do fish for smallmouth and use the same for tippet material too. There is another question to be answered when it comes to fluorocarbon and that is what is the difference between a 100 yard / 200 yard spool of Fluo. which is made for conventional reels, ex. spinning reel vs the small 25 yard spool of “tippet” material from Rio. and others. Does fluorocarbon made by the fly fish companies (RIO as an example) have a more strict quality control, line diameter more constant.?
The price is a factor for sure.

Aug 24, 2017

Frank Brooks:

On the subject of mono vs fluoro, I can attest that using mono in the saltwater here in Maine will deteriorate faster than the fluoro leader. The fluoro feels more soft and flexible after days of use.
I believe I lost all those trophy stripers I had on the line when using mono. Anyway, thats my story and I’m sticking with it!
Good article, thanks Josh

Aug 23, 2017

Leave a comment