Understanding Fly Lines: The Heartbeat of Fly Fishing

// Header image by Christian Anwander

Last updated on May 5th, 2024.

Leonard Schoenberger
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What makes fly fishing unique is that you rely on the weight of the line to carry a nearly weightless fly to your target.

Getting to know the different types of fly lines and their specific purposes is essential for anglers at all levels.

Why is the Fly Line so Important?

Filson Guide Vest Fish on
A fly line is crucial in fly fishing since it is the weight with which you get your fly to the fish. Photo: Christian Anwander

Think of a fly line as more than just a string to throw your fly; it’s a sophisticated tool crafted to deliver your fly exactly where you need it, either gently or with a bit of force, depending on what the situation demands. The right fly line improves your control over how the fly lands and helps you manage different environments and fish species. It’s designed to perform specific functions, like floating or sinking, and suits the type of casting you plan to do.

Fly Fishing Etiquette: Always approach the water silently
Understanding fly lines: Casting a streamer into a Montana stream. Photo: Shane Rickert

Single-Hand Fly Lines: What Are Your Options?

Weight Forward Fly Lines (WF)

What are they? These lines have a heavier and thicker front end which tapers to a thinner back end. This design helps you cast longer distances since the weight is concentrated at the front.

Why use them? They’re great for beginners because they’re easy to handle and work well in a variety of fishing scenarios. They work particularly well for streamer fishing. WF lines comes as floating lines, intermediate lines and sinking lines. This differentiation enables you to fish different depths of the water columns depending on the species you target.

A fly fisherman casting from a fishing float tube
Understanding fly lines: A weight forward line is a good option to generate some distance.

Double-Taper Fly Lines (DT)

What are they? Double-taper lines are symmetrically tapered at both ends with a longer middle section that’s level. This design allows you to reverse the line if one end wears out.

Why use them? They’re excellent for making delicate presentations and are good for roll casting, though they aren’t the best for long-distance casting. I like them a lot for bamboo fly rods and fiberglass fly rods. They are also great for intermediate and advanced fly anglers to present a dry fly.

Fly fisherman holding a trout
Bamboo fly rods often have a slightly slower action that works well with double-taper fly lines. Photo: Dave Westburg

Shooting Heads

What are they? This line type has the main weight concentrated in the first 30 feet, followed by a thinner running line.

Why use them? Ideal for making long casts with minimal backcasting space. They’re especially handy in saltwater fly fishing and when targeting larger freshwater species. Just like weight forward lines, shooting heads come as floating, intermediate and sinking lines.

Fly fishermen walking along the shore
Understanding fly lines: When fishing in the salt, a shooting head can faciliate casting (into the wind). Photo: Marco de Sao Vicente

Fly Lines for Double-Handed Rods

Fly fisherman casting a double-handed spey rod

Double-handed rods, like those used for Spey casting, need a different type of line:

Spey Lines

What are they? These are longer and heavier, designed to complement the length and power of double-handed rods.

Why use them? Spey lines are perfect for casting large flies over long distances, especially useful in big rivers where you’re limited in backcasting space. For salmon fishermen, I recommend spey lines with interchangeable heads so you can adapt to the conditions. In colder, high water surroundings a sinking head might get you down to the fish whereas in the summer months, an intermediate or floating head might work better.

Specialty Fly Lines: Tailor Your Gear

Fly Reel with Fly Box and Bag
In the saltwater you tend to fish with heavier fly lines. Photo: Christian Anwander

Nymph Lines

What are they? These lines are longer with a unique taper that aids in placing nymphs precisely.

Why use them? They’re perfect for achieving the right depth and flow in streams, enhancing the natural movement of the nymph.

Understanding fly lines: fly fisherman nymphing in a river
For nymph fishing a fly line with a smaller diameter works better as your drift will be more natural. Photo: Leonard Schoenberger

Wrapping It Up

Choosing the right fly line is crucial—it significantly influences your casting technique, the types of flies you can use, and ultimately your success in catching fish. With so many fly lines available, you can fine-tune your gear for any fishing condition or technique.

FAQs: Understanding Fly Lines

How do I pick the right weight fly line for my rod?

Always match the fly line weight to what’s recommended on your rod. This ensures optimal performance and balance.

Can I use double-taper lines for long casts?

Double-taper lines aren’t ideal for long casts. They excel in precision and delicate presentations for shorter distances.

What’s the biggest advantage of using a weight forward line?

Weight forward lines make casting easier and allow you to cast farther, especially in windy conditions or when using larger flies.

Why choose a nymph line over a standard floating line?

Nymph lines are specifically designed to enhance nymph fishing, offering better control over line placement and drift, making your nymph presentation more natural.

How often should I replace my fly line?

Depending on usage and maintenance, replace your fly line every 2 to 3 seasons, or sooner if it shows signs of wear or damage.