Can You Use a Saltwater Fly Line in Freshwater?

Choosing a fly line is always an important subject matter in fly fishing. And since saltwater fish have more fighting power than freshwater fish, one question readily comes to mind: can you use a saltwater fly line in freshwater?

You can use a saltwater fly line in freshwater. Saltwater fly lines are sturdy enough to withstand the fight of saltwater fish. In the event of fishing in cold water environments, you may notice saltwater fly lines will begin to coil. This is because saltwater fly lines are typically designed for tropical environments.

In this article, I’ll show you all you need to know about fly lines – saltwater or freshwater. I’ll also distinguish the different types in terms of durability so I can help you make an informed choice. 

saltwater fly lines are sturdy

Saltwater Fly Lines vs. Freshwater Fly Lines

Saltwater and freshwater fly lines are designed differently to fit their purposes. While you can use saltwater lines for freshwater fishing, you can’t use freshwater lines for saltwater fishing.

Saltwater Fly Lines

Due to the high salinity of saltwater, saltwater fly lines are sturdy and are built with non-corrosive materials. These lines are adequate for saltwater fish with high fighting strength and weight.

Saltwater fly lines are measured in weights, ranging from WF6–WF12. The fly line and fishing rod should have compatible weights. However, the weight of the line and rod depends on the species and location of the target fish.

Saltwater fly lines are designed for warmer water. While some lines used in salt are designed for cooler water, they are not intended for snowy or icy environments. Saltwater lines are generally stiffer than their freshwater counterparts. This is due to the tendency of Saltwater fly lines soften when placed in warmer elements.

Freshwater Fly Lines

Freshwater fly lines are purpose-built for only freshwater fish. They are less dense, extensive in diameter, and can float on the water. They are suitable for use in clean, non-corrosive water. Therefore, using freshwater fly lines in saltwater will only reduce their lifespan.

Freshwater Fly Line or Saltwater Fly Line: Which Is More Durable?

Saltwater lines and freshwater lines are built for different environments. However, freshwater lines tend to last longer since they are used in non-corrosive water and contend with smaller fishes.

Whether saltwater or freshwater, fly lines can be used 100–250 times before replacement. However, some care tips can help you elongate the lifespan of your fly line.

  • Fly lines will last longer when used according to their purpose. If you want your fly line to last, stick to the appropriate environment. This is more critical for freshwater fly lines that have no protection from corrosive environments.
  • The secret to the longer lifespan of your lines is proper cleaning. Always clean the line after every use. Regular cleaning keeps your fly line free of sand or debris.
  • Clean saltwater lines with fresh water immediately after every use. Never forget to clean it, so the salt water doesn’t settle on the line and cause dry rot.
  • If your line has been curled up for over a month, bring it out and stretch it to release the stiffness.
  • Unknot any wind knot you notice on your line. Wind knots weaken the line and may cause it to break when fishing.
  • Limit exposure to UV rays. It depletes the coating on the line, causing it to wear and break down quickly.
  • Casting your line on hard surfaces or rocks and sand can cause damage to it over time. Check your line at the end of the day for any cuts.

Pro Tip: For cleaning your fly line, the Scientific Anglers Fly Line Dressing makes the job easy and quick. Simply run your fly line through the lubricated pads to clean your line and create a slick coating.

fly lines come in different types

Types of Fly Lines

Fly lines come in different types. Three of the most popular include:

  • Floating fly lines
  • Sinking fly lines
  • Intermediate fly lines

Let’s go over each one of them.

Floating Fly Lines

As the name implies, these lines float on water. These lines are the most popular and generally all that is needed for saltwater fly fishing. You’ll want to use floating lines with lightweight flies for fishing higher in the column, however you can fish a sinking fly on a floating line in order to reach the bottom in shallower water..

Sinking Fly Lines

Sinking lines sink when cast into the water. It’s ideal for catching fish that reside deep in the water column. Sinking tips are lines designed for fishing the middle of the water column, where only the fly is needed to get down quickly. Sinking types are commonly found with 9-15ft sinking sections.Sinking lines are classified into two:

  • Full sink: Every part of this line sinks into the water when fishing.
  • Sink tip line: Only the tip of this line sinks. The other parts float on water.

Intermediate Fly Lines

Intermediate lines are similar to sink tip lines as they are designed to fish higher in the column, yet not near the surface. The difference between a sink tip and and a full intermediate is that the entire line sinks when fishing a full intermediate as opposed to just the last couple of feet.

Choosing a Suitable Fly Line

Whether you’re going freshwater or saltwater fishing, fly lines are the second most important thing you need.

You need to know a few things before choosing a suitable fly line, especially if you’re new to fishing:

  • The weight of your fly line must sync with the weight of your rod. If you have a 9wt rod, you’ll need a 9wt fly line.
  • Choose a fly line that matches the temperature of the water you want to fish in. There is a line designed for each water temperature, whether it is cold, warm, or saltwater.
  • Buy a fly line that suits your fishing environment. Get saltwater fly lines specifically designed for saltwater fishing and freshwater fly lines designed for freshwater fishing.Most manufacturers even design lines to target specific species.
  • Get a fly line that can cast the fly you intend to use. The fly you get will depend on the species of fish you’re targeting. Sometimes a shorter taper line is needed to deliver larger flies quickly. 

Pro Tip: Scientific Anglers makes cutting edge fly lines for any application or species. I have used them for years and can vouch for their durability and quality.

you should buy a fly line that works for your needs


Saltwater fly lines are stronger than freshwater lines and can withstand tough fish. Therefore, you can use saltwater lines in freshwater.

Freshwater lines are built for smaller fish and for non-corrosive water. Saltwater lines, on the other hand, are built for bigger fish and are designed with materials that resist corrosion.

The fly line should match the fishing experience. Intermediate lines are a great choice if you’re new to fly fishing.

You also want to give your lines the needed cleaning and care to extend their life. Else, you’ll need to replace your lines regularly.