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Getting Started In Fly Fishing - Choosing A Fly Line

How To Fly Fish Series: How to choose the right fly line for your fishing

by Fly Fisherman Magazine  |  January 3rd, 2017



Fly Lines

In spin fishing, the line is a nearly weightless monofilament trailing behind a relatively heavy lure. In fly casting, the weight and energy is in the fly line itself, which makes the line an essential consideration.

In terms of casting performance, fly lines are perhaps even more important than the rod you use. Unfortunately, some intermediate and even advanced casters use lines that are worn out or lines designed for other purposes. Don’t make these mistakes. Expert casters replace their lines when they lose their buoyancy or slickness. As a beginner, you don’t need the extra challenge of an old, worn out fly line.

Tiny microspheres make floating lines bouyant. The core gives the line its strength. Darell Wilson Illustration

If you are new to fly fishing, and want to get started fishing for trout in rivers and streams, your first fly line will likely be a general-purpose floating weight-forward freshwater line such as Scientific Anglers Trout, RIO Gold, Cortland Trout Precision, or Orvis Generation 3 Trout. These high-quality floating lines are designed to meet the needs of most trout stream anglers. You can use them for dry-fly fishing, nymphing, and most streamer fishing.

Sinking lines have tungsten flecks in the coating to make them dense. Darell Wilson Illustration


Taking the Next Step

As you progress as a fly fisher you will need more than a general-purpose floating line. For instance, most floating trout lines are poor choices to cast bass popping bugs, catch trout in deep water, or catch steelhead and salmon in large swift rivers.

Before you can make a wise purchasing decision for a specialty fly line, it’s helpful to know how the lines are built, and how the core, coating, and taper of each line affect performance.

Core. Think of the core as the skeleton of the fly line. It gives the line all its strength, determines how much or how little it stretches, and also determines how flexible it is. Fly lines with monofilament cores generally have less stretch and are less flexible (stiffer) than lines with multifilament cores. Stiff lines cast farther because they “shoot” better and tangle less frequently. In cold weather and in cold water, however, lines with monofilament cores often have too much memory, leaving you with coils that are difficult to cast. Monofilament-core lines are therefore best suited for hot weather or tropical species like bonefish.

Lines for trout and other coldwater species are most often made with multifilament cores which gives the line manufacturer more control over how much memory the line has, how much stretch it has, and how stiff (or limp) it is.

There are a few lines out there with no-stretch cores made of Kevlar or other materials. The benefits, say manufacturers, are solid, quicker hook-sets on fish, and performance casting due to the fact there is no stretch to drain energy from your casting stroke. The downside is that if you can’t stretch the line, it’s difficult to remove line coils after you strip it from your reel. No-stretch cores might have someadvantages but have never really caught on with the general angling public and you should probably avoid them while you are learning to fly fish.


A weight-forward line has a narrow rear running line and a thin tip section. The head carries most of the line mass and determines the line weight.


Coating. The coating is the plastic covering the manufacturer applies over the fly line core. Most line companies use polyvinylchloride (PVC) for the fly line coating—the same PVC used for everything from making credit cards to household pipes. PVC can be made soft and flexible by adding plasticizers and you can make it slippery by adding lubricants. Most fly line companies have their own propriety combinations of these ingredients to produce the line qualities they are looking for.

[The U.K. company Airflo does not use PVC as a base material for its fly line coatings. Airflo uses polyurethane; a polymer it says is more durable and resistant to cracking. Cortland has a single specialty saltwater line made of a proprietary blend of polyethylene that is inherently buoyant. The resulting line has an overall smaller diameter which means it has less wind resistance, and creates less disturbance when it hits the water. Cortland says the polyethylene coating has a lower coefficient of friction and shoots farther than PVC-coated floating lines, and that polyethylene is more durable and abrasion-resistant than PVC lines. The Editor.]

By varying the plasticizers in the PVC coating, manufacturers can also make a fly line more or less stiff. A line advertised as a bonefish line should have a stiffer coating that still shoots through the guides when it is 95 degrees F. and won’t turn gummy and more prone to tangling. Trout lines are specifically designed to perform best in cold water.

The fly line coating—or rather, what a manufacturer adds to the fly line coating—also determines whether a fly line floats or sinks. Manufacturers can add tungsten powder to create a dense line that sinks, or add glass microspheres to make a less dense floating fly line. Manufacturers also combine these materials to make a line with a tip that sinks and a floating rear portion.

[Tiny glass spheres have been the industry standard for decades but RIO recently began making fly lines with an additional buoyancy material it calls AgentX. As part of its Super Floatation Technology (SFT), RIO uses glass microspheres on the interior of the coating and AgentX in the exterior. The result, RIO says, is a higher-floating fly line that is also smoother since it doesn’t have the microbumps associated with microspheres. The Editor.]

While some companies go the extra mile making their lines smooth, Scientific Anglers has recently unveiled a whole series of Sharkskin lines with a textured surface you can hear going through the rod guides, and feel with your hands. According to SA, the textured surface reduces friction because only the high points rub against the rod guides, and Sharkskin floats higher because of the way the ridges create contact points with the water’s surface.


The lines illustrated above show some of the characteristics that can help you fish more effectively from top to bottom. Shown (left to right) are the profiles of a weight-forward floating line; a weight-forward floating line with a short, clear intermediate tip; an intermediate-tip line; a fast-sinking tip line; a fast-sinking shooting taper; and a super fast-sinking shooting taper.


Taper. A fly line’s taper directly affects the way it shoots, turns over a heavy fly, presents a small fly delicately, or casts efficiently at long or short distances. The line taper (its outside dimension) is the result of varying thicknesses of the line coating—some parts are thicker and have greater mass, other parts are thin and have less mass. This distribution of mass along the length of the line determines how the line will perform in a variety of conditions. For instance, if you want the line to easily cast a large, wind-resistant bass popper, you need most of the line weight as close to the fly as possible. This additional mass, concentrated at the head of the line, helps turn over large flies during the final delivery. However, this is not ideal for fishing small flies on flat trout water where you need a long, delicate tip for stealthy presentations.

There are two major groups of fly-line tapers: weight-forward and double-taper. Double-taper lines are economical and sufficient for most short- to medium-range fishing situations but have fallen out of favor with most fly fishers because they are not the best lines for making long casts.

Weight-forward lines cannot be reversed like double-taper lines. They have a narrow, level-diameter running line at the rear that shoots through the guides easily allowing for longer casts. The head of the fly line includes the front taper that starts at the tip and gradually increases in diameter; the belly, where most of the weight is concentrated; and the rear taper that decreases in diameter as it joins the rear running line. Look for the abbreviated WF on your fly line box to determine if it is a weight-forward line.

Weight-forward tapers include nearly every specialty line on the market, including lines made for bass, tarpon, steelhead, salmon, trout, and pike. If you want to make your casting as easy as possible and enjoy productive fishing, choose the weight-forward specialty line that matches your situation. If you are fishing for trout, get a line advertised as a trout line. If you plan on fishing for bass, you will be frustrated trying to cast large bass bugs with anything other than a bass line. It isn’t just a marketing ploy—there are significant differences between the various specialty lines.

(top to bottom): A weight-forward line, double-taper line, a weight-forward line with a compound front taper, and a shooting taper.


Shooting Tapers

Think of shooting-tapers as radical weight-forward lines designed for distance casting. They still have a thin running line and all the weight up front, but the transition is more severe. Shooting tapers—often called shooting heads—are typically heavier than a regular weight-forward line, and the running line is thinner and lighter.

Often, the shooting head itself is separate from the running line and you connect the two using a loop-to-loop system. This allows you to keep a single running line on your reel and change the shooting head from floating to sinking, or from one weight to another depending on the fishing situation. A sinking shooting-taper with a floating running line can also be called a sinking-tip line.

Some shooting tapers are integrated, which means the shooting head and the running line are contiguous just like a regular fly line. These lines still have the same casting characteristics as other shooting tapers but there is no loop connection to jam up in the rod guides. The disadvantage is that if you want to change an integrated shooting taper you must replace the whole line. You can’t just change the head of the fly line.

Sky Blue or Sunset Orange?

Which color of fly line should you buy? If you are just getting started, you should use a brightly-colored fly line you can easily see in the air and on the water. The easier it is for you to see your fly line, the easier it will be for you to improve your casting and presentations. It can also help you locate your fly, detect strikes, and determine whether your fly may be dragging or not.

Trout can see colors, but most of the time color is far less important than a heavy splashdown or the shadow caused by a moving line. This is especially true on most American waters where the clarity is not always perfect and there is frequent flotsam in the water the trout deal with every day.

In New Zealand—where the water is famously clear and often free of floating weeds, sticks and logs, and other debris—a fluorescent fly line can spook trout. Guides there insist on using drab, olive-colored lines to avoid spooking trout.

Fly lines with monofilament cores can have a clear coating. “Clear” may seem to be the best color in terms of not spooking fish, but an all-clear line serves little purpose since in most cases the trout only sees your leader. Clear sinking-tips or clear full-sinking lines for lake or saltwater fishing can be an advantage since you can use a short leader and gain more control over the depth of your fly without sacrificing stealth.

Getting Deeper

Trout, bass, steelhead, and many other fish come to the surface for exciting moments of topwater feeding, but most of the time they skulk deep, not feeding, or feeding only occasionally on food items that come to them. Using a floating line is a pleasure, but if you want to catch fish regularly, you need to get down to them. In fly fishing, there are two general ways to do this: You can either use your floating line with a long leader and attach weight (split-shot usually) near the fly end of the leader, or you can use a sinking line and allow the weight of the line to sink the fly to the fish.

In shallow water up to 2 or 3 feet deep, a floating line with a weighted fly, or a fly and split-shot attached 6 to 12 inches above it works fine for both dead-drifted and swimming flies.

In moving water from 3 to 6 feet deep you can effectively probe the bottom by dead-drifting flies with a weighted nymph rig. At this depth in moving water, streamers and other swimming flies tend to ride up too high in the water column unless you use an unwieldy amount of split-shot. An alternative is to use a sinking or sinking-tip line.

As mentioned previously, sinking lines have tungsten powder in the line coating which makes them denser than water. (Sinking lines originally contained lead powder but tungsten is heavier and less toxic.)

Sinking lines fall through the water column at different rates, from intermediate 1.25 to 1.75 inches per sec­ond (ips) to fast-sinking 4.5 to 6 ips. Extremely fast-sinking lines sink as fast as from 7 to 10 ips.

Some sinking lines are marketed by their grain weight—300-grain, 400-grain, etc.—but don’t be fooled by the weight of the fly line. Grain weight helps you match the line to the rod but the grain weight isn’t what makes fly lines sink—there are 750-grain floating lines out there. It’s the density of the fly line that causes it to sink, so match the grain weight to your rod weight (see chart on page 10) and match the sink rate (in inches per second) to your fishing situation.

Full-sink­ing lines are best suited to fishing in stillwaters (lakes and ponds). They are designed to get flies down to the level where the fish are feeding, which could be 1 foot under the surface or 60 feet under. When you are fish­ing over sandy shallows 1 to 3 feet deep, you may want to use an intermediate line to keep the fly where the fish are feeding while avoiding hanging up on the bottom. If the weather is extremely hot, and trout are holding in the cool depths of the lake, you’ll need a fast-sinking line to get down to them. An extremely fast-sinking line that sinks at 10 ips will take around 12 seconds to get the fly 10 feet deep, so you’ll have to use the countdown method: Cast, then count to 12 to get the fly where you want it.

Lines that sink uniformly (evenly) or tip first are the best lines for fishing stillwaters. Because they sink in a straight line, they allow you to detect strikes easier and set the hook more efficiently.

Some sinking lines do not sink uniformly: The middle sinks faster than the thin, less dense tip, creating a U-shaped belly that can cause you to miss strikes. When the fish takes the fly, the tension may take up some slack in the belly while the angler doesn’t feel anything.

Most modern full-sinking lines sink uniformly to provide a straight-line
connection to the fly, allowing you to detect a high percentage of strikes and thus catch more fish.


Sinking-tip lines have a front sinking portion connected to a rear floating line. They are better in flowing water than full-sinking lines because you can mend and control the rear portion of the fly line while the tip continues to sink to the fish’s level. Sinking tips range from intermediate- to fast-sinking to bring the fly to the fish through a variety of both depths and currents.

Since it takes time for fly lines to sink, you’ll need a fast-sinking tip to get your fly down to the fish quickly in fast-moving water.

The length of the sinking portion determines not how quickly the line sinks, but the final depth of the fly. Because the line sinks at an angle from the base of the floating portion to the tip of the fly line, a longer sinking portion will ultimately get deeper. For instance, a 30-foot sinking-tip section that sinks at 5 ips will get your fly much deeper in the water column than a 10-foot sinking section with the same sink rate.

Sinking-tips are extremely important pieces of equipment for West Coast steelheaders who use them to swim flies slow and deep in the water column. Pacific salmon fall to the same strategies and no angler should visit British Columbia or Alaska without a full compliment of sinking-tip lines for 8- to 10-weight rods.

Striped bass fisherman who fish off jetties and in deep tidal rips also require fast-sinking-tip lines to reach the fish. Trout fishermen use them to “pound the banks” from drift boats, to fish streamers in deep holes, and billfish anglers use the weight of heavy sinking shooting-tapers to deliver extremely large flies quickly at short distances.

Cleaning Your Fly Line

Fly lines collect dirt, algae, and salt. A clean line floats higher, casts farther, mends more easily, and will last longer since things like dirt and salt are abrasive.

Fly lines should be cleaned regularly with warm water and a mild soap such as Ivory. Wipe the line with a soft cloth.

RIO sells a fly line dressing to coat the fly after you clean it. Cortland sells a Fly Line Cleaner Pad that does everything in one step. Scientific Anglers sells a line cleaning pad and line dressing package.

It was once popular to clean fly lines with automotive products such as
Armor All or other cleaner/protectors, but fly line manufacturers tell us the opposite. Harsh soaps can dry and crack fly lines. Automotive products may make your line slicker immediately after treatment, but in the long run deplasticize the line, making it crack prematurely.

At the end of the fishing season clean all your lines and wind them back onto their original line spools or store them in loose coils. Always store your lines out of direct sunlight. Ultraviolet light and high heat (a hot car trunk, for instance) can cause the line coating to deteriorate swiftly. With proper care your lines should last from three to five years under normal use. Anglers who fish more than 100 days per year may replace their primary lines annually to get maximum performance.