Copolymer Vs Monofilament Fishing Line

If you are new to fishing then all the different lines available may be a little confusing. There’s braid, monofilament (mono), fluorocarbon (fluoro) and copolymer lines. What are they all, what makes each one different and better than the one before and when should you use each one?

Making the right choice about your line is key to your success as a fisherman and today we are going to look at the difference between copolymer and monofilament.

copolymer vs monofilament

What are they made of?

First things first, what are each of these lines made of?

They are both made from nylon and using the same process of taking nylon and stretching it out to form a long line. The difference between the two is in the nylon used for the stretching. Mono is, as the name would suggest, made of one type of nylon and copolymer is made up of two different types of nylon.

Using two types of nylon allows the manufacturers to experiment to try to find the best combination that will give the line the attributes we fishermen want. Thanks to this, copolymer lines are generally better than monofilament lines and here is why.

Why are copolymer lines better?

The main things we look for in a line as fishermen are strength, diameter, durability, stretch, visibility and abrasion resistance. Copolymer lines are ahead of mono in all of these factors and here is why.


Thanks to the merging two types of nylon before making copolymer lines it is overall a lot stronger than monofilament and fluorocarbon. Generally speaking, copolymer lines have a high level of impact resistance, abrasion resistance and they do not snap easily. They are not the strongest lines on the market, braided lines are a bit stronger but what is impressive is their combination of strength and impact resistance as a lot of lines usually don’t have one and the other.


This is directly related to the strength funnily enough. Thanks to copolymers being stronger, it allows the line diameter to be thinner than mono or fluoro. The diameter of a copolymer line is usually about two or three times thinner than an equivalent mono line of the same strength.

This means you can fit a lot more line on your reel. If your reel is rated for say 250 yds of 20lb mono, you’ll be able to fit 500-750 yds of 20lb copolymer on there. This means you can target bigger fish that take long runs and increase your casting distance without the worry of having a light spool of line left over.


Stretch is important in a line and is what gives line it’s impact resistance. You want a little bit of stretch in a line but not too much. Copolymer line stretches a little when under pressure and doesn’t just snap like a stong stiff line would. This means that when snagged on the bottom or pulling up a stubborn fish, it will give a little and allow you to play the situation instead of just breaking. Stanard mono, on the other hand, is a bit stretchier than copolymer, which will give you more give but less of a direct connection.


Visibility in the water is all about a line’s refraction index. The higher the refraction index the less visible the line will be in the water. A copolymer line isn’t bad at refracting light and it does a much better job than mono. This means it will be seen less easily by fish than mono, giving you a better chance of catching them.


Durability is about several factors and overall mono and copolymer lines will need to be changed every year. After a year, sun, sea, and fish will have gotten to it and it’ll be weak. Where copolymers do win though is in water resistance.

You may not think that a nylon line would absorb water but they do. The longer a line sits in the water the more it will absorb. Copolymer will absorb less water than mono which is useful if you need a line that is submerged a long time, for example, if you are bottom fishing. This means it will stay strong and solid for longer than mono even if it’s underwater a lot.


Copolymer lines do sink faster than mono lines which is a benefit in some situations and a negative in others. If you are planning on fishing with a float or surface lures then a line that sinks isn’t going to be very useful. Buty if you are bottom fishing or jigging, a line that sinks is going to be far more useful.


All fishing lines have some memory in them and this refers to then shape a line retains. If you pull a line off a reel and it remains in coils, it has a bad or high memory. If it comes off the reel and sits straight, then it has a good or low memory. This has huge advantages when it comes to casting and reducing tangles as those coils will wrap themselves around anything they get near to and add friction to your cast.

Copolymer lines have a much lower memory than mono lines. It doesn’t have the lowest memory of all lines out there but it’s pretty good at retaining its shape even when it’s sat on a reel for a long time.


The sensitivity of a line refers to its stretch. The more a line stretches the less direct contact you will have to what’s on the end of it. Copolymer line is more sensitive than mono as it is a bit stiffer and therefore gives you a more direct feel to the end of your line. This is very useful when you want to feel sensitive bites from fish or need to put a lot of pressure on a fish to pull it up from the depths.


Overall, copolymer is more expensive than mono but it is better and it’s cheaper than braid. It’s a winner in my book and worth the extra cash.


It looks like copolymer wins the battle against mono. It’s better in every way except for cost and if you are surface fishing, as it will sink. If were you, I’d chose it over mono every day of the week.



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