The fly line must match the recommended line weight of the fly rod. Aside from weight, the taper, buoyancy, and color should be considered.

The taper of the fly line dictates how a fly line will cast. Fly lines with a weight-forward taper are designed to propel flies with conventional false casting. Fly lines with a double-taper allow for increased ease when roll casting.

Fly lines come in floating and sinking varieties. Most fishing situations require a floating line however sinking lines are useful in certain situations. All beginning anglers should begin with a floating line to master both dry fly and nymph fishing. Sinking lines are used to fish streamers or saltwater patterns. Because of their weight, they are more difficult to cast and require an experienced-casting angler.

The color of the fly line is another personal preference. Many anglers use dark colored fly lines in gray or green hues to disguise their lines against the sky or the foliage surrounding a stream. These lines are less visible to fish and to the angler. Angler’s with inferior eyesight often prefer more brightly colored fly lines in tan, orange, yellow, or white hues. Less emphasis should be placed on color than on the previous aspects of the fly line.