Fly Fishing 101

Floating vs Sinking Fly Line for Trout: Which Do You Need?

Daniel Bowman Updated November 4, 2026 10 min read

Fly line is the part of a fly fishing setup most beginners think about least. It also does more work than almost anything else. The line carries the cast, and it decides how deep your fly fishes.

This guide sorts out the four kinds of line you'll see, what each one is for, how fast the sinking ones sink, what they cost on the makers' own sites, and which one fits each kind of water we fish in North Georgia. Prices and specs were checked on November 4, 2026. If you'd rather try the gear on a guided day before you spend anything, our trip finder is the place to start. Rods, reels, flies and terminal gear are provided.

What are the four kinds of fly line?

Floating, intermediate, sink-tip and full sinking. Orvis's fly line guide puts the basic split simply: "Some lines float, some sink, and some have a sink tip, so the front end drops while the rest stays higher."

In plain terms:

Cortland describes its intermediate-tip line as "designed to effectively fish the middle to upper water column on rivers and lakes." A full sinking line like RIO's Premier Fathom is sold for lakes.

Why is floating line the default for trout?

Because it does almost everything a trout angler needs. A dry fly has to float, and so does the line behind it. A nymph rig works off a floating line too, with weight on the leader to get the fly down.

Orvis's guide says to "start simple: match a weight-forward (WF) line to your rod weight," and gives the example "A 5-weight rod = WF5F (floating) for most freshwater." It also notes that "a floating line can work with weighted flies, but it's slow to reach depth." Cortland's streamer guide says to "choose a floating line for smaller water like streams and creeks."

So if you're buying your first line, buy floating. You can fish a whole season on it.

Which line goes with which fly?

Here's the quick match, using the makers' guidance above:

• Dry flies: floating line, always. The fly has to ride on the surface.
• Nymphs: floating line, with weight on the leader or a beadhead fly to get down.
• Small or weighted streamers in small water: floating line. Orvis notes a floating line with a weighted fly "can be the easier, cleaner setup."
• Bigger streamers in deep or fast rivers: a sink-tip, per Cortland's "bigger bodies of water with faster currents and deeper holes."
• Lakes: an intermediate line for the upper water column, or a full sinking line like RIO's Fathom for deeper presentations.

If most of what you fish is on the first three lines of that list, one floating line does the job.

When does a sink-tip line pay off?

When you're fishing streamers in water too deep or fast for a floating line to reach. A streamer is a fly that imitates a small fish, and big trout often eat them near the bottom of deep runs.

Cortland's streamer guide says "choosing a sink tip line is best when fishing in bigger bodies of water with faster currents and deeper holes." Orvis's streamer tackle lesson agrees: "In smaller rivers and shallower water floating line will work OK," while a sink-tip lets you fish more of the water where big fish hide.

Signs a sink-tip would help:

• You're fishing streamers in a deep pool and never feel the bottom.
• The current is fast, and a weighted fly on a floating line swings up before it gets down.
• You're casting from a boat to deep banks and seams.
• You're fishing a big, heavy fly that needs to track straight at depth.

If none of those describe your fishing, you don't need one yet.

How fast do sinking lines sink?

Fly line makers rate sinking lines in inches per second. Here are the numbers from the makers' own pages:

RIO's own article on streamer lines uses the same type numbers: a Type 3 tip "sinks 3 inches/second" and "the Type 6 sinks, yep, 6 inches/second."

What that means on the water, as rough arithmetic: count five seconds after your cast lands, and a Type 3 tip is about 15 to 20 inches down, while a Type 6 is about 30 inches down. Current, fly weight and line angle all change that, so treat it as a starting point, not a measurement.

Cortland's intermediate tip sinks much more slowly, at 1.5 to 2 inches per second.

How do you fish a sink-tip once you have one?

A few habits from the makers' guides:

1. Shorten the leader to four or five feet, Cortland's maximum for sink-tips.
2. Count it down. For the middle of a river where you can't see bottom, RIO's streamer article suggests a fast-sinking Type 6 tip and a count before you start the retrieve. Note the count that finds fish, and repeat it.
3. Mend the floating part. The Orvis lesson describes a line with "a short, fast sinking head with a floating line behind," which makes the fly easier to mend.

A longer count fishes the fly deeper, so change one thing at a time.

What's the cheapest way to try sinking line?

A sinking leader on the floating line you already own. RIO's Trout VersiLeader is $15.99, and RIO calls it "the ultimate versatile leader system for quickly adjusting sink rate on the end of typical floating trout lines." It comes in floating, intermediate and two sinking versions.

Compare that to a dedicated sink-tip line at $89 to $99.95 in the table above. For a trout angler who fishes streamers now and then, the leader is the low-cost way to find out whether you need more.

What leader goes with each line?

A longer one on floating line, a shorter one on a sink-tip. Cortland's streamer guide says: "We recommend using a leader between six and nine feet" on a floating line, and "between four to five feet maximum on sink tip lines." The Orvis streamer lesson gives the same direction: a nine-foot leader works with floating line, and sink-tips call for a shorter one.

The reason is simple. A long leader on a sink-tip lets the fly ride up, away from the depth the sinking tip just reached. Our guide to leaders and tippet covers the floating-line side in detail.

Weight-forward or double taper?

For most trout fishing, weight-forward. "Taper" is how the line's thickness changes along its length.

Orvis explains the difference on its fly line guide:

• Weight-forward (WF): it "loads the rod quickly and helps most anglers cast with less effort, especially at typical fishing distances."
• Double taper (DT): "for short, delicate dry-fly work, a double taper (DT) line is hard to beat."

Orvis's Hydros Trout Double Taper page adds one practical perk: "the ability to reverse the line to extend its life," since both ends are the same. Our article on rod weight for North Georgia trout covers taper in the context of matching a whole setup.

How do you match a line to your rod?

By the number. Orvis says "a 5-weight rod uses a 5-weight line, a 6-weight uses a 6-weight, and so on." Line weight is printed on the rod near the handle and on the line box.

Orvis also mentions one exception some anglers use: going one size heavier, which "is called overlining." It "can help some anglers feel the rod load and make short-to-mid casts easier." For a first line, stick to the matching number.

Your reel has to hold the line too. Our trout reel comparison covers reel sizing.

What is backing, and do trout anglers need it?

Backing is thin, strong line that sits on the reel under the fly line. It's there for when a fish runs farther than the fly line is long. Orvis's backing page says its backing is "braided Dacron," and that "20-lb. test is for trout, bass, and most freshwater fishing," while "30-lb. test is great for steelhead, salmon, bonefish, stripers, and more."

Most trout won't take you into your backing. Big fish can, and on our private water, where trout often run 17 inches or more, it's worth having it on the reel. On our striper page, we describe "fish that might show you your backing."

What does a floating trout line cost?

About $49 to $98 on Orvis's site. Here are four, checked November 4, 2026:

All four are from one maker, Orvis, because that's where we could confirm current prices. Orvis calls the Clearwater "a versatile option for the budget-minded angler" and says the Hydros Trout "stays clean, casts easily, and mends well."

What are the tradeoffs of each line, side by side?

Floating line, from the makers' descriptions:

• Good at: dry flies, nymph rigs, mending, small water.
• Weak at: getting a fly deep fast. Orvis says it's "slow to reach depth" with weighted flies.

Sink-tip line:

• Good at: streamers in deep, fast water, where Cortland says it's "best."
• Weak at: dry flies, and it needs a shorter leader.

Full sinking line:

• Good at: lakes, which is what RIO sells its Premier Fathom for.
• Weak at: most river trout fishing, which the makers' guides pair with floating or sink-tip lines instead.

For a river trout angler, that usually means one floating line now and a sink-tip later, if streamers become a habit.

What should you check before you buy a line?

Five questions settle most line purchases:

1. What weight is my rod? Buy that number.
2. Floating or sinking? Floating, unless you fish streamers in deep or fast water, in which case a sink-tip. Full sinking is the lake line.
3. Weight-forward or double taper? Weight-forward, unless you fish short dry-fly casts on small creeks.
4. Does my reel have room? Line plus backing has to fit.
5. Could a sinking leader do the job first? At $15.99, it's worth trying before an $89 to $99.95 sink-tip line.

Which line fits each kind of North Georgia water?

Mostly floating, with a sinking line for one kind of trip. Below, the makers' guidance is laid over the rivers we guide. Only the Tuckasegee and striper rows are our own line recommendations; the rest apply the makers' general rules.

Striper days are the exception: an 8 or 9 weight rod, a sink-tip or intermediate line, and big articulated streamers of 4 to 6 inches. For bass on the same trips, "a 6 or 7 weight with a floating line is good to have."

Our guide to stripping a streamer covers how to fish a sink-tip once you have one.

Do you need any of this for a guided trip?

No. On our trips, "we provide all rods, reels, flies, and terminal gear," and our rates page says all trips include "gear, instruction, and everything you need." Your guide sets you up for the day's water.

That makes a trip a good way to try gear before buying it. On a striper float, you'll cast a sink-tip or intermediate line on a heavy rod, and on the Tuckasegee, we recommend a floating line on a 5 or 6 weight. Anglers 16 and older generally need a fishing license, and on Georgia trout water a trout license too, per Georgia DNR's license page.

Daniel Bowman

Owner & Head Guide · Bowman Fly Fishing

Daniel has guided fly fishing trips in North Georgia for more than 10 years. He runs Bowman Fly Fishing with a team of 10 guides on the Toccoa, Soque, Etowah, Noontootla, and Tuckasegee — including private water access most anglers never get to fish.