Billfish Sinking

$99.95 USD Save

The new Tropic Plus “Billfish Sinking” line features a 30ft heavy sinking head with a bright orange tip to track your fly through the prop wash. The 50lb braided nylon core gives you extreme stopping power. Built with our premium tropic jacket material allowing the line to stay stiff and slick in the hottest conditions.

- Hi-Vis Tip
- 30ft Sinking Head
- Fifty Pound Plus Core

WATER: Saltwater
LINE: Sinking / Floating 
TAPER: Weight Forward
LENGTH: 90ft
CORE: Braided Nylon Multifilament
SPECIES: Billfish / Sailfish / Marlin

Size WF 13 - 15 / 600 GRAINS

United States deliveries usually take 3-8 business days.

International deliveries can take up to 7 - 18 days.

If you have any question about shipping Contact Us our customer service department is here to help.

 P65 - WARNING: Cancer and Reproductive Harm

Saltwater Sinking Weight Forward Monofilament

WF 13-15 600 gr. 34 ft. 6 in. 90 ft.

Billfish Sinking Breakdown

We designed the Billfish Sinking to deliver large flies into the middle water column of the prop wash.

This line features a 3 ft. type 6 sinking head with an 18 in. Hi-Vis orange tip for tracking your line through the prop. A short 3 ft. back taper allows this line to load quickly and efficiently hitting your target with ease.

Built on a 50lb braid core for ultimate stopping power and durability, the Billfish Sinking features our tropic plus coating and thin profile that cuts through the water quickly with minimal line drag. This line is offered in a grain weight of 600.

SPECIES: BIllfish / Sailfish / Marlin


Welded loops make rigging fast, easy and reliable. Cortland loops are strong, secure and durable.


ST coating delivers a reduced-friction performance with a glass-smooth finish and remains a key element in line slickness over its life span.


The perfect blend of advanced polymers to achieve a hard, durable surface that remains slick in extreme heat.


Built for the most demanding species. Core strength of more than 50lbs allows anglers to put maximum drag and pressure on a fish without compromising the taper design or line density.


Ideal use in 50 - 70 degree (F) temperatures


Ideal use in 70 + degree (F) temperatures

Our Billfish Sinking line is built for tropic environments and will perform best in temperatures above 70 degrees (F). Our Tropic PVC coating is designed to remain hard, slick and supple in the hottest conditions.

The taper design for our Tropic Plus Billfish sinking line was built to cut through wind and water quickly. The 30 ft. type 6 sinking head gets your fly down fast with minimal line drag. This line is built in a 13-15 wt. to load powerful, offshore fly rods.

The Hi-Vis Orange tip and running line allows for easily tracing your fly in the prop wash.

Cleaning your fly line is very important especially when fishing saltwater. Simply pull line off your reel into a clean bucket or tub of freshwater. Put roughly 1oz or more of Cortland’s Line Cleaner solution onto a clean rag or towel. Firmly squeeze the towel with Pro Line Cleaner around the line and slowly pull line through the towel. You should be able to see dirt or discolored streaks on the towel when finished.

Learn more about Cortland's Fly Line Cleaner Lubricant & Pads.

Hover: Neutral
Slow Intermediate: 1 IPS (Inches Per Second) 
Medium Intermediate: 1.5 - 2 IPS (Inches Per Second)
Fast Intermediate: 2 - 3 IPS (Inches Per Second)
Type 3 Sink Rate: 3 - 4 IPS (Inches Per Second)
Type 4 Sink Rate: 4 - 5 IPS (Inches Per Second)
Type 5 Sink Rate: 5 - 6 IPS (Inches Per Second)
Type 6 Sink Rate: 6 - 7 IPS (Inches Per Second)
Type 7 Sink Rate: 7 - 8 IPS (Inches Per Second)
Type 9 Sink Rate: 9+ IPS (Inches Per Second)

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Based on 1 review
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1 Review
Reviewed by Jeff L.
Verified Buyer
I recommend this product
Rated 5 out of 5
Review posted

Just the Ticket

I have been searching for a quality fast sinking line to get down in the water column. Between boat drift and current it was difficult at best. This Billfish line suited my needs perfectly. Fast enough sink rate to stay in touch with my fly, and still very manageable casting on my 12 wt to reasonable distances. If you need to get down to those holding deep I can't think of a better line. Highly recommended. This snapper would agree.

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