The Gallatin is way up and dirty and will be for a while now. I would maybe think about heading to a different spot for now but if you do really wanna get on the Gallatin the further up river you go the better. It will be best way up above the Taylors Fork. Nymphing is gonna be your best bet I would fish a rubber leg or a worm down to some shiny nymphs like Lite Brite perdigons in red, purple, or pink. The water is to cold and dirty for any good dry fly fishing but once it clears you can start to throw some chubby dropper rigs. Throwing some small shiny streamers like Sparkle Minnows could turn up some fish.
Gallatin River Webcam - Located at Karst, which is about 1/2 way between Bozeman and Big Sky on HWY 191.
Fins & Feathers is a full-service Bozeman fly shop and Montana fly fishing outfitter. Gallatin River fly fishing trips are available year-round with our Bozeman fly fishing guides. Montana fishing licenses are available for purchase online at Montana Fish, Wildlife & Parks & in our Bozeman Fly Shop (some exceptions may apply). If you are planning to fish in the headwaters of the Gallatin River area above Taylor's Fork (approx. 1 mile upstream); be aware that most of this is in Yellowstone National Park which requires a separate fishing license and is seasonally open to fishing according to YNP regulations.
Fishing from a boat is not allowed on the Gallatin River from the headwaters downstream to the confluence of the West (main-stem) and East Gallatin River, however it is permissible to use a boat/craft for access for wade-fishing in this stretch of the river. Fishing from a boat is allowed downstream of this point to the rivers mouth. Bob's Shuttle provides shuttle service (seasonal) between Manhattan and Three Forks on the Gallatin River and can be reached at 406-595-0587 via voice or text. In general, shuttles should be arrange the day prior or before 9 am the morning of your departure.
The Gallatin River is one of the more scenic, blue-ribbon trout waters found in the Bozeman area. The river changes in character from a small mountain stream near its headwaters in Yellowstone National Park to a medium-sized, classic western river once it flows into the Gallatin Valley. The middle portion of the river flows through the Gallatin Canyon and is characterized by pocket water and swift currents. Once it leaves the canyon stretch, the river slows its pace with much of the trout water being found in a classic riffle, pool, and run water types. The Gallatin River is noted for having very clean, cold water throughout its course and served as the setting in which much of "A River Runs Through It" was filmed.