The Best Sinking Fly Lines – Get Down to The Fish! (2021 Guide)


We’ve all been there. Sat for hours, not a single fish showing on the surface. Where could they be?

Well, I’ll tell you.

Deep down on the bottom.

A floating line just isn’t going to cut it. You will have to take the fly to the fish and to do that, you will need the best sinking fly line.

I’ve taken a look at a few great fly lines that will work well, and I’m going to tell you what areas are worth considering when buying.

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Stuck for Time? – Sinking Fly Line Quick Guide

Sinking fly lines are pretty straightforward. If you’ve seen my article on the best floating lines, you’ll already be well in the picture.

If not, here are the things you need to consider.

fisherman wearing waders and sunglasses fly fishing in river

Castability

I’ll start simple.

If you can’t get the line out to the fish or can’t present your fly correctly, it doesn’t matter how ‘good’ your line is.

You will need a line that is easy to cast with a nice finish.

Sink Rate

Depending on your venue, you might need to consider your options.

A fast current or very deep water will require a line that sinks quickly. Conversely, shallow or slow-moving water might need a line that is steadier in its sink rate.

Look for the rating in IPS, which stands for inches per second.

Line Size and Rod Pairing

This one’s interesting. You aren’t going to find a sinking line under #4WT. Try and fit a heavier sinking line to a too-light rod, and you will end up with one thing and one thing only…

Breakages.

I’ll explain more in my detailed guide below.

Price

Let’s face it, this might be the determining factor.

Here’s my advice. Get the best you can afford.

Why?

The best rod and reel in the world, from the best brand, can’t outperform a poor quality line. If you have a cheap setup or fish infrequently, you might not notice the difference. But it would be a shame to invest in a beautiful rod and reel combo, only to be let down by your line.

Ok, with the above in mind, let’s take a look at a few good options…

Top 5 Best Sinking Fly Lines 2021

Scientific Anglers Wetcel Type IV

I like the name ‘scientific anglers’… It gives images of fishing being a systematic method.

These guys are fast becoming a big player in fly fishing. Compared to a Rio fly line, I am hard-pressed to see much of a difference.

And here’s the thing…

Bearing in mind that this line retails for around half the cost, I think that is pretty excellent value.

Compared to fly lines of the past, there are a few clever features in this sinking fly line. For a start, it is a grey charcoal color. So, you aren’t going to spook the fish by flashing a neon green stripe past them on the way down.

If you are fishing wet flies, there’s a good chance that you’ll be tying on a big old streamer. For this reason, you are going to need a weight forward line… Exactly like this.

This line will sink at 5 inches per second. That’s nearly 30 feet per minute. So, if you want to get hard down on the bottom, it will do the job well.

Pros

  • Fast sink rate, perfect for deep water and fast flows.
  • I like the color.
  • I really like the price, it’s great value.

Cons

  • It is only available up to weight #5 and above. If you have a lighter rod, I’d advise against using it.

Takeaway

Scientific anglers produce gear that is just as good as the ‘big’ names, without the ‘big’ price tag. I was pretty impressed with this one, a good fly line for the money.

RIO Products Fathom 6 Sinking Fly Line

While I’m on the subject of ‘big’ names, take a look at this.

They don’t get much better than Rio if we are talking fly lines.

If you are fishing heavy in big water, this line will be ideal as it is rated as WT#6. You are going to pay a premium price, but you’ll get great value and unbeatable performance.

Here’s why.

It’s a weight forward line with a super dense ‘shooting head’. In real terms, this means you’ll be able to cast further without as many false casts.

Rio has created a variable density within the line. This allows it to sink consistently, regardless of how much you have cast out. A nice additional feature is an anti-tangle core. Tangles can be a real pain with cheaper lines.

One really nice feature is the ‘hang marker’. This small mark is easy to see and lets you know how deep you are if you are looking to fish areas with a shelf or drop-off.

Oh, and naturally, with Rio, it casts like a dream.

Pros

  • One of the best sinking fly lines for streamers.
  • Easy distance and casting.
  • The anti-tangle core makes it really easy to use.

Cons

  • Honestly? From a performance point of view, it is pretty perfect… I just wish it was cheaper!

Takeaway

I’ll be upfront. I don’t actually mind paying for quality. This is a case in point. As sinking fly lines go, this is about as good as it gets. Give it a try. You won’t regret it.

SF Full Sinking Fly Fishing Line

Ever sunk your fly past the fish?

Yeah, it happens.

The answer is a fly line that combines the control of a floating line with the depth penetration of a sinking line. Also known as a ‘sinking tip’.

This line isn’t fancy or a big name brand, but for such a low price, it is worth having tucked away in your bag when the fish can’t make their mind up.

This PVC coated braid is ideal for nymph fishing and fishing big streamers subsurface.

The bright orange finish makes it easy to see what’s happening. Speaking of the finish, it is a little unusual, as it does feel slightly ‘plasticky’. Still, it seems to cast pretty well, and it will get a fly down under the water quite easily.

One neat feature is that the line type is embossed on the leader loop. Making for easy identification when you are selecting how you want to fish.

Pros

  • Great value.
  • Easy to see.
  • It works to get the fly down below the surface.
  • It’s available in WT#4.

Cons

  • The finish of the line is a little unorthodox. It feels quite hard and stiff.

Takeaway

Looking for the best sink tip fly line can be tricky, as it has to satisfy a lot more than a plain sinking or floating fly line. Bearing in mind the price, this fly line bridges the gap quite nicely, without breaking the bank.

Scientific Anglers Type III Full Sinking Line

I loved scientific angler’s efforts so much I just had to include another one.

But what’s the difference?

Oh, only the opportunity to catch more fish!

First off, let us look at cosmetics. The color of this line is slightly different. Dark green is great when fishing areas of heavy foliage, and especially amongst the weeds.

The sink rate is also tweaked. This sinks at 3 inches per second. This is a little slower than my previous suggestion, giving you more control, especially in slower moving waters and shallower pools.

It is very much a weight-forward line, so if you are looking to heft out a big lure, it will work extremely well.

Pros

  • Slower sink rate for more control.
  • Dark green, great for avoiding spooking the trout.
  • It’s severely weight forward, making it really easy to cast.

Cons

  • Again, it is only available down to WT#5.
  • I can’t see why it is more expensive than the other scientific angler lines.

Takeaway

Everyone should have an intermediate sinking fly line in their bag. It lets you fish in the depths but with a good degree of control.

This is still cheaper than a Rio line and occupies a great middle-ground between performance and budget. One of the best fishing lines for trout on the market.

Aventik Sinking Tip Fly Line

Listen, I get it…

Not everyone wants to blow $80 on a fishing line.

If you don’t fish that often (why not?), it might make sense to go for something a little cheaper.

This line by Aventik sinks is strong and durable, and hey, do you know what? I think it looks really great.

For the money, you’ll get out and fishing, and that’s what counts, right?

The first 15 feet of this line sinks. The rest is floating, giving you a large degree of flexibility in how you fish. It is particularly useful for fishing streamers when trying to create that ‘up and down’ effect on the lure.

One thing I like is that this line doesn’t have a lot of stretch. This will allow you to feel every knock and pull, just what you need when you can’t see your fly.

Considering the price, it casts pretty well too. Don’t get me wrong, it isn’t going to be anywhere close to Rio in terms of performance. Still, for a rough and ready budget solution, it does the trick quite nicely.

Pros

  • Low price.
  • Good casting performance.
  • The sinking tip is great for imparting action on a lure.

Cons

  • Let us be honest, It’s a cheap line. It will work, but chances are you will want to upgrade at some point. Meaning you’ve paid for two lines.

Takeaway

You know me. You get what you pay for. For a beginner or an angler who wants to get set up at minimum cost, this one is well worth a look… Just don’t expect it to be your ‘forever’ line.

How to Choose a Sinking Fly Line

Alright. The world of fly lines is far more complex than it first seems. There are numbers and letters all over the place, and fishing is hard enough without the jargon.

I want to make it easy for you.

Here’s a handy guide to give you all the information you need on choosing the best sinking fly line.

fisherman holding fly fishing rod

Choose the Right Weight

Notice anything about the above list of sinking fly lines?

Not a single one goes lighter than a #4wt!

Here’s why…

Sinking fly lines are a lot heavier than their floating counterparts. This is obviously going to put stress on your rod.

Add into the mix that you might have 30ft of the line under the water, and that’s a lot of weight to be hauling up whenever you pull back to start your cast.

Here’s a simple truth.

Lighter fly rods aren’t made for that. The answer is to avoid going too heavy with your line weight. You won’t get away with using a Wt#4 sinking line with a #3 rod. It just isn’t going to happen.

And by that, I mean… You will break your rod.

If you think you might want to use a sinking fly line, make sure you get a rod that can handle it. #5wt rods are a great compromise as you can fish floating lines too, and they work in any venue.

Full Sink or Sinking Tip?

There’s an element of personal preference here, but how you fish is largely dictated by where you fish.

If you are fishing in 40 feet of water and the trout are on the bottom, you won’t see much joy with a sink tip. It simply won’t reach them. In that case, a full sink is going to be your best bet.

If your local ‘spot’ is only 15 feet deep, using a fast sinking high-density fly line is probably overkill. You simply won’t need to be getting down to the bottom so quickly.

Both a sinking tip and a full sink will allow you to reach the fish… I just go for an intermediate, full sink line for my money, then I’m covered from the top of the water down to the bottom.

man casting rod and fly fishing in river

Sink Rate

Inches per second?

Sounds a bit technical?

Trust me, it’s easy. This is a measure often given as the acronym ‘IPS’. It is a measure of how fast the line descends through the water column.

Here’s an easy rule of thumb to remember.

If it’s a big number, say, above 6, it’s the fastest sinking fly line.

But what to go for?

Here, do yourself a favor and make life easy. A 3 or 4 IPS line will cover you for 90% of the subsurface fishing you do. You’ll normally find that lines rated in this range are also a good weight to pair with most mid-ranged rods.

Quality

The line is actually one of the most important parts of your setup.

After all, it keeps you connected to the fish. In fly fishing, there are also other things to consider.

Like?

Like the ease of casting and presentation, your line plays a massive part in this. And here is why I’m talking about quality. One word…

Memory.

Cheap lines suffer from memory. This is where they take on a certain shape. If it is anything other than straight, you aren’t fishing effectively.

Higher quality lines are made from compounds that resist memory.

If you don’t know what ‘memory’ is on a line, here’s a real quick video guide that explains it:

Leader Loops

If you didn’t know already, your flies aren’t tied directly to the fly line. They are attached to a leader.

Ideally, you want a fly line with a leader loop to make life easy when down on the water.

It isn’t a deal-breaker, however, if you need to learn how to tie your own, here’s a quick video guide:

Color

Color is important when choosing a sinking fly line.

Why?

Unlike with floating fly lines, you are literally going to be dragging it past the fish’s nose! For that reason, dull colors are the order of the day. I particularly like drab greens and greys. I find that these spook the fish least.

FAQs

I get asked about sinking fly lines a lot. Here are some things people often want to know.

What is sinking fly line used for?

Sinking fly lines are generally used for sub-surface fishing. You can use a floating line, but if the fish are deep down in the water, it can be hard to reach them. You could try using a long leader, but that becomes pretty unmanageable for casting (especially in strong winds).

The answer is a sinking fly line. The entire line will sink down through the water column. It is actually a really effective way to fish. If you know how fast your line sinks per second, you can count in your head. This is a great technique to find out what depth the fish are feeding at.

In 90% of cases, you’ll use a sinking fly line with a lure, streamer, or nymph.

How do I choose a sinking fly line?

The first place to check which line you need is to look on or near your rod handle. You’ll be able to identify which weight line you need (and if your rod is heavy enough to accommodate a sinking line).

From there, you need to think about where and how you want to fish. This will dictate the sink rate of your line.

What’s next?

From there, you can focus on budget and will need to search for the right line, fitting the above criteria, at a price that you consider great value.

A word to the wise… Get the best fly line that you can afford. It may seem like great economy to pick up a $9 brand, but you will notice a vast decrease in performance.

Cheaper’ no name’ fly lines tend to perform poorly when casting, are less strong, and are much more prone to getting ‘memory’. Not fun when you are trying to enjoy yourself.

How do I store a fly line?

Here’s the thing about sinking fly line.

It gets wet (like, duh).

Over time, being kept cold and wet can damage it. Further to this, fly lines don’t take kindly to being wrapped up tight on a spool over winter.

The best way to store fly line for extended periods is to hang it in loose coils on a peg or hook. If you don’t want to spool it back on every time, it might be time to invest in a reel with a large arbor.

These styles of reels are becoming ever more popular. They put less pressure on the line and actually make it easier to cast too.

How do you cast a full sinking fly line?

Honestly?

If you’ve picked a good sinking fly line, there is little difference in casting technique. You might find it slightly heavier than your normal floating fly line. All that said, if you pick a quality line from a well-known manufacturer, the difference is really minimal.

Summary

I fly fish for all sorts of species. If you like bass, I’ve got an article on the best bass fly lines right here.

With a sinking line and a floating line, you’ll be well equipped to catch whatever the conditions.

Fishing with a sinking line can often mean the difference between catching something decent and a ‘blank’ day.

Stick to my buying guide above and consider some of my suggestions. With brands such as ‘Rio’, you can be sure that they are the best sinking fly lines around.

Do you catch bigger on floating or sinking? Let me know in the comments. I’m always looking for tips to up my game!

Bob Hoffmann

The author of this post is Bob Hoffmann. Bob has spend most of his childhood fishing with his father and now share all his knowledge with other anglers. Feel free to leave a comment below.

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