RIO Fly Lines and Backing

Who RIO is

RIO's story page says Jim and Kitty Vincent founded the company in 1990 in the mountains of Idaho, and that every one of its fly lines is made in its Idaho Falls facility. Far Bank's account of its own history says Far Bank was formed in 2005 as the holding company for Sage, Redington and RIO, so RIO belongs to the same family as those two. None of this tells you anything about how a given line casts, but it does tell you where to look for the maker's own words, which is why most of our maker links go to farbank.com.

What RIO sells on Amazon US now

At our last check (October 2026) we track 28 RIO listings on Amazon US: 21 fly lines and 7 spools of backing. There are no RIO rods, reels or kits in our data, so this is a lines-and-backing page.

In the table above, each value carries a small mark. "Maker" means a RIO page states it, "listing" means only the Amazon listing says so, and "—" means we could not confirm it. Most RIO lines here are marked "listing", because the Amazon title tells you the weight and taper (WF4F, for example) but the maker's page is not linked for every model. Where a RIO page does exist, the table and the text below use it.

How to read a fly line listing

Four things matter, and the listing title usually gives you three of them.

• Weight. A number from 1 to 15 that tells you which rod the line is made for. Match it to the rod's printed line weight. The fly line weight chart shows what each number is for.
• Taper. WF means weight forward: the thick part is near the front, which makes casting at distance easier. DT means double taper, with a thick middle and thin ends, which suits short, delicate casts and can be reversed when one end wears. ST and "running line" refer to shooting-style lines.
• Density. F is floating, I is intermediate (a slow sinking line), S is sinking, and F/S or "sink tip" is a floating line with a sinking front section. For most trout fishing you want F.
• Core. The braided or monofilament centre that gives a line its stretch, strength and feel. Many lines list a core, and some listings do not.

Our types of fly line guide covers the rest, and the floating line page lists floating lines from every brand.

RIO Gold fly line

There are three Gold lines in the RIO catalog that we track. They share a name and a purpose, which is trout, and it is easy to buy the wrong one. (Elite Gold, Premier Gold and Avid Trout Gold are three different lines with the same colour name, so read the second word.)

Premier Gold. The maker calls it an all-round trout line, standard weight and standard power, sold in weights 2 to 9. The page describes a longer head and lighter weight than the XP and MAX versions, with a 47-foot head and a long back taper, a mid-length front taper of 5 feet 6 inches on the WF5F, and a front taper designed for flies from size 22 to size 2. It carries the maker's SlickCast coating, and the page claims it has the lowest friction the maker has measured. It also lists MaxFloat Tip technology, which the maker says keeps the tip floating higher. The maker names small dry flies and dry-dropper fishing as the primary uses, and big dry flies and light indicators as secondary.

Elite Gold. The maker's page describes an all-around trout line, in weights 4 to 8, with a long head and long back taper, a 5-foot-6 front taper, the SlickCast coating and a low-stretch ConnectCore Plus core. The page says the core improves sensitivity for detecting takes, setting hooks and controlling fish. The stated uses are the same as Premier Gold. The page's own head-length figures for the 4-weight and for the WF5F do not match exactly, so I will not quote one.

Avid Trout Gold. Our data has only the Amazon listing for the WF4F: a weight-forward floating line, with no maker page.

The practical difference is the core and the weight range. If you fish a 3-weight, Premier Gold is the one of the two with maker pages that comes in that weight. If you want the maker-stated core, Elite Gold names one.

Mainstream, Avid and the entry lines

The Mainstream family is the older entry-level range in our data: Mainstream Trout in WF4F, a double taper DT4 and a full-sinking Type 6 WF6S6, a Bass/Pike/Panfish WF7F, a Saltwater 10 and a Striper WF10I, which is intermediate. Every value in these rows comes from the Amazon listing, because no maker page is linked. The Avid range adds an Avid Trout Gold WF4F and a 24-foot sinking tip line described as slow sinking. Premier Perception WF7F and Premier Creek WF3F are also listing-only.

The fair way to read these rows is as starting points. A Mainstream or Avid line tells you the weight, taper and density the listing states. If you have a particular fish and rod in mind, find the maker page for that line before you buy.

Euro nymph, indicator and specialty lines

FIPS Euro Nymph. The maker's page lists an 80-foot, 2 to 5 weight floating line with a thin, low-stretch, supple core, a highly visible tip and a one-size-fits-all design for European-style nymphing. It says Steve Parrot designed it, and that FIPS Mouche approved it as competition legal, with line marks that mean you do not need line checks at a competition. Our euro nymphing setup guide shows where a line like this sits in the rig.

Euro Nymph Shorty. A listing-only 2 to 5 weight floating line in our data. I could not find a maker page for it, so I cannot say how it differs.

Elite Indicator. A WF5F with a 4 to 8 weight range in the listing, floating, with the ConnectCore Plus core named in our data.

SlickShooter. A 25 pound running line, listed as a running-line taper. A running line is the thin part behind a shooting head. It is for people who already know why they want one.

Predator and saltwater lines

The heavier end of the range has five lines in our data.

• Elite Predator WF8F. A floating weight-forward line with ConnectCore Plus, with a range of 5 to 11 on the listing.
• Elite Flats Pro 10. A floating line with a DirectCore and a 6 to 12 range.
• Elite Leviathan 12/13. A DirectCore line in the 12 to 13 range.
• Elite Salmon/Steelhead WF10F. A floating WF10 with ConnectCore Plus, described by name for salmon and steelhead.
• Premier OutBound Short WF6F/H/I. A multi-density line with a 5 to 12 range on the listing.

Whether a line is a good fit for a given fish is the maker's claim, not our test. If you are matching a line to a rod for a fish like redfish or steelhead, our redfish rod weight and steelhead rod weight pages explain how the weights relate.

RIO fly line backing

Backing is the line under the fly line. It fills the spool so the fly line does not coil too tightly, and it is your reserve if a fish runs past the end of the fly line. (It is the spare tire of the reel: you buy it, load it, and hope never to meet it.)

RIO's Dacron backing, per the maker's page, is a traditional braided Dacron in 20 and 30 pound test, 100, 200 and 300 yards, which the maker says has high strength and low stretch and balances thinness with the ability to form blind splice loops. It adds that it is easier to knot than very thin backings with a tighter weave. We track Dacron in 20 pound at 100 and 200 yards and 30 pound at 100 and 300 yards.

RIO's multi-color gel spun backing is listed at 65 pound test in 100, 200 and 300 yards. Gel spun is thinner for a given strength, so more of it fits on a small spool. The maker's page for gel spun is linked in our data, but we did not read its text, so the Amazon listing is the source for these values.

How much you need depends on the reel and the line. Our backing page lists backing from other brands, and the guides on how much backing to put on a fly reel, the backing knot and spooling a reel cover the rest.

Care and how long a line lasts

A fly line is a coated cord, and the coating wears. Dirt, sunscreen and heat all shorten its life. Keep it clean, and replace it when it cracks or stops floating. Our guides to how long fly line lasts and how to clean a fly line explain how, and I would read them before you decide a line has "gone bad".

Warranty

We could not confirm a RIO warranty for fly lines. Far Bank's warranty policy page lists sections for Sage and Redington rods, reels and wading gear, and none for RIO products. If the terms matter to you, ask Far Bank before you buy. Keep your receipt in either case.

How to choose a RIO line

• Small to medium trout river, dry flies and dry-dropper. Premier Gold or Elite Gold, in the weight your rod is rated for.
• Tight-line nymphing. The FIPS Euro Nymph, if your rod is a 2 to 5 weight.
• Bass, pike, panfish. The Mainstream Bass/Pike/Panfish is the listing for a 7-weight.
• Warm saltwater. Elite Flats Pro or the Mainstream Saltwater, in the weight your rod calls for.
• Anything with a fish bigger than your reel. Check backing capacity before you order the line.

For more choice, the fly lines section lists other brands, and our fly line weight chart shows how a number maps to a rod.