Gallatin River Fishing Report
Gallatin River Fishing Report
9/26/2025
Cooler overnight temps and cooler water temps mean happy trout and good streamer fishing. No better time to get out and fish!
As of late, the weather, river conditions, and happy trout have been providing some awesome late summer fishing opportunity. With a rain shower here and there during most weeks, we see a small increase in river lows and a small drop in river clarity. Whenever these rain showers happen and we get enough precipitation for the river to lose some clarity, the fishin tends to get really good. The trout will move around a lot in the river during these times and will eat significantly larger patterns.
Super early mornings it can be pretty chilly in the canyon stretches of the Gallatin River and there is not much reason to try and get out at the crack of dawn. We don't see too much feeding activity from these fish until the sunlight starts to hit the water. Right now the best way to have a fun day on the river is to start with some streamers, switch over to a nymph rig once that bite slows down, and then in the afternoon when is warms up and the sun is fully out to switch to a hopper dropper. While the hopper bite is not as good as it was in weeks past, you can still get a few fish to rise to it and you might as well throw it cause who doesn't love to see a dry fly eat?
If you are having a slow day, try downsizing your fly patterns. The only real bug activity we get this time of year is going to be from small mayflies like Tricos and Blue Winged Olives. Midge activity is a steady option and will work great during the cool mornings as we get closer to winter. We aren't too far out from having some October Caddis start hatching and if you flip over a rock, you will likely find lots of their larvae right now.
Unsure of what you should be using on the river today? Check out our pattern suggestions below or swing by our shop in Big Sky for some advice!
Dries: Chubby Chernobyl (Royal, Black/Purple) #16, Galloup's Butch Caddis (Tan) #14-16, Bloom's Parachute Caddis (Tan, Dark Olive) #14-16, Micro Chubby (Olive, Gold, Royal, Black/Purple) #14-18, Skater Tot (Royal Purple, Black Purple, Black Tan, Olive) #14, RIO's Dry Humper (Royal, Royal Purple) #14, Glo Ant #18, Jake's Gulp Beetle (Red, Blue, Purple) #14
Nymphs:Pat's Rubberlegs (Black, Coffee, Brown) #8-12, BH Pheasant Tail CDC #14-16, Perdigons (Spanish Bullet, Lite Brite, Pearl and Black, Butano, Olsen's Blue Steel, Gasolina), Purple Haze Covey #18, Lightning Bug #14-18, Little Green Machine (Pheasant Tail, Gray, Chartruese) #18, Galloup's Hare's Ear (Olive) #18-20
Streamers: Boogieman (Rootbeer) #4, Galloup's Two Tone Dungeon #4-8, Double Screamer (Olive, Black, Gold) #6, Wooly Bugger (olive, black)#10, Sparring Partner (Black/Purple) #6
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Updated reports for the Gallatin River coming to you from our backyard in beautiful Big Sky, Montana. We know this river like the back of our hands.
