Updated: October 5, 2026
Fall fishing is in full swing on the Bitterroot. The river is low, clear, and in excellent shape for October, with cool nights keeping water temperatures comfortable and the fish active. Current flows are roughly 230–240 CFS near Darby, 465–475 CFS at Bell Crossing, and around 900 CFS near Missoula.
This is one of our favorite times of year to fish the Bitterroot. Angler traffic has dropped off, the valley is quiet, and there are still some excellent opportunities to fish dry flies. With the lower flows and clear water, longer leaders, lighter tippet, and accurate presentations will make a noticeable difference.
Hatches
Blue-Winged Olives (BWOs) are becoming increasingly important, especially during cloudy or cooler weather. Look for fish rising in slower tailouts, foam lines, riffle edges, and slicks. Small BWO dries and emergers in the #18–22 range are worth having ready.
Mahogany Duns are starting to become a factor and should continue improving as we move deeper into October. October Caddis are also around, particularly on the upper river and forks. Hecubas can still make an appearance as well.
Don't put the terrestrial box away just yet. Warm, sunny afternoons can still produce fish on ants, beetles, and the occasional hopper, especially along grassy banks and deeper undercuts.
Dry Fly Fishing
The best dry-fly window is generally late morning through the afternoon. There's no reason to rush to the river at daylight right now. Give the water and air temperatures some time to warm up and watch for bugs before committing to a setup.
When fish begin rising, a single dry on a longer leader is often more effective than pounding the water with a large attractor. On cloudy days, keep an eye out for concentrated BWO activity.
Nymphing
A dry-dropper remains a dependable way to cover water between hatches. Small Pheasant Tails, Perdigons, Frenchies, BWO nymphs, Hare's Ears, and October Caddis pupae are all good choices.
Concentrate on riffle edges, inside seams, deeper buckets, foam lines, and the transition water between faster riffles and slower pools.
Streamers
Streamer fishing is becoming more interesting as we get farther into fall. Try small sculpins, Woolly Buggers, Thin Mints, Sparkle Minnows, and smaller articulated patterns.
Olive and black are good starting colors. Work deeper banks, shelves, buckets, and structure, especially during low-light periods or when clouds move in.
Flies to Have
Dries: BWO #18–22, Mahogany Dun #14–16, October Caddis #8–12, Parachute Adams #14–20, Purple Haze #14–20, ants #14–18, beetles #12–16.
Nymphs: Pheasant Tail #16–20, Frenchie #14–18, Perdigon #16–20, BWO nymph #18–22, October Caddis Pupa #8–12, Jig Hare's Ear #14–18.
Streamers: Thin Mint, Woolly Bugger, Sparkle Minnow, Sculpzilla, Mini Dungeon and small olive or black sculpin patterns.
Freestone's Take
This is classic fall fishing on the Bitterroot. Low, clear water means you may have to work a little harder for your fish, but the reward can be excellent dry-fly fishing with very few people around.
Slow down, watch the water before casting, and don't overlook subtle rises in tailouts and slicks. Cloudy afternoons are the days we're especially excited about right now—that's when the fall mayfly fishing can really come alive.
Stop by Freestone Fly Shop in Hamilton before heading out and we'll get you dialed in with the latest flies and information from the river.
