Spanning 692 miles from the Absaroka Range in Wyoming to its confluence with the Missouri near the North Dakota border, the Yellowstone is the longest undammed river in the contiguous United States. In Montana it slices through iconic Paradise Valley, Yankee Jim Canyon, and the vast cottonwood bottoms east of Livingston, offering year-round trout water framed by snow-capped peaks and rolling prairie. Consistent flows, diverse hatches, and abundant public access make this blue-ribbon stream equally inviting to first-time anglers and seasoned veterans seeking big browns on big water.
Anglers divide the river into three character zones. **Upper River (Park boundary to Gardiner)** tumbles through canyons of pocket water ideal for walk-wading and late-summer terrestrials. **Paradise Valley (Gardiner to Livingston)** meanders beneath the Absarokas with wide riffle-run glides and famous salmonfly action in early July. **Lower River (Livingston to Big Timber and beyond)** broadens into cottonwood flats where drift-boats target trophy browns with streamers and hoppers. East of Billings the river warms, shifting toward smallmouth, sauger, and catfish while still offering underrated late-season trout pods.
The upper reaches harbor wild rainbow and brown trout to 22 inches alongside native Yellowstone cutthroat and mountain whitefish. Downstream of Livingston browns dominate, with rainbows and cuttbows mixed in riffles and side channels. Warm-water stretches below Huntley Dam add sauger, channel catfish, smallmouth bass, and even the occasional walleye. Native cutthroat and whitefish remain conservation priorities throughout the basin, while bull trout are rare transients requiring immediate release if encountered.
Mother’s-Day caddis in late April blanket the water and jump-start surface feeding. Early July brings explosive salmonflies and golden stones, followed by PMDs, yellow sallies, and dense evening caddis swarms. Hopper-ant-beetle combos dominate from mid-July through September, especially during windy afternoons in Paradise Valley. Autumn browns chase sculpin streamers before winter midge and blue-winged olive hatches reward patient nymphers. Matching these predictable food cycles—or fishing larger attractor dries when clarity runs green-gold—keeps rods bent all season.
A fast 9-foot 6-weight shines for tossing big stonefly dries, heavy nymph rigs, and articulated streamers, while a 5-weight suits technical dry-fly work on calm days. Early-season nymphing with rubber-legs and stonefly larvae probes deeper seams; switch to chubbies or Salmonfly imitations tight to willows when water temps climb above 55 °F. From July through frost, drift-boat anglers bang foam hoppers against banks, while waders sight-cast small caddis or BWO emergers in slicks. Sink-tips or trout Spey lines swing sculpins and olive dungeons for trophy browns at dawn or dusk.
Paradise Valley put-ins such as Carbella, Emigrant, Pine Creek, and Grey Owl provide classic float-and-wade water with easy shuttles along US-89. Yankee Jim Canyon challenges skilled rowers but rewards with solitude and big stonefly eats. Downstream, Carter’s Bridge and Mayor’s Landing near Livingston are productive walk-in options. Mid-river islands around Springdale and Big Timber hold cuttbows eager for hoppers, while towns like Forsyth and Miles City give late-season anglers a chance at warm-water species on big streamers.
Montana FWP maintains more than 40 Fishing Access Sites (FAS) between Gardiner and Laurel, most with concrete ramps, vault toilets, and primitive camps. The FAS guide highlights distances, amenities, and river-mile markers—essential for planning safe float lengths. In the sparsely serviced lower reaches, boaters must sometimes cover 20 miles between launches, so carry extra fuel and provisions. Always check the FWP restrictions page for high-water or wildfire closures before launching.
Carry a quiver of dries from size 6 chubby Chernobyls and salmonfly imitations to size 18 BWO comparaduns. Rubber-leg stones, prince nymphs, and wire-worm droppers cover subsurface, while olive or black sculpin streamers move big browns. Leaders: 9-ft 3X for hoppers, 4X–5X for PMDs and caddis, 0X with a 5-ft sink tip for articulated dungeons. Felt or studded soles are critical on the river’s greased-bowling-ball rocks; a wading staff is invaluable. Polarized glasses help spot trout on sun-glared flats.
Heavy runoff events, invasive species, and agricultural de-watering threaten the Yellowstone’s cold-water integrity. Trout Unlimited’s **Yellowstone Basin Initiative** secures side-channel reconnection and riparian restoration, while the **Greater Yellowstone Coalition** advocates for Wild-and-Scenic protections and opposes new mines in headwater tributaries. Anglers can help by decontaminating boats to curb aquatic invasives, respecting seasonal hoot-owl closures when water exceeds 73 °F, and volunteering for annual river clean-ups.
Spring snow-melt can push flows above 15,000 CFS—well beyond safe rowing for most rafts. Downed cottonwoods create deadly sweepers after ice-outs, and afternoon winds can generate three-foot rollers east of Livingston. Lower-river stretches have long float distances with limited bailout points; pack spare oars and a repair kit. Always check FWP closure notices and NOAA flood advisories before launching, wear a PFD, and avoid anchoring in swift water.
**Yellowstone Angler** (Livingston) offers daily reports, shuttles, and specialty streamer patterns. **Sweetwater Fly Shop** sits riverfront south of Livingston with classes, rentals, and a friendly gear staff. **Montana Angler** in Bozeman guides the upper and lower river, providing custom multi-day float packages and hatch intel. All three shops welcome beginners, supply updated flows and clarity, and can arrange professional instruction or DIY shuttle logistics.
Get involved locally through **Montana Trout Unlimited**, which coordinates 13 volunteer chapters statewide on habitat projects, including Yellowstone River side-channel reconnections. The **Greater Yellowstone Coalition** mobilizes community science and policy advocacy to keep the river wild and free. Nationally, **Trout Unlimited’s Yellowstone Basin Initiative** funds scientific monitoring and post-flood restoration efforts. Donations, citizen science, and river-clean-up days are powerful ways to give back to this storied fishery.
The Yellowstone River outside the national-park boundary is open year-round. Daily limit 5 trout in combination, only 1 over 18 inches (cutthroat release strongly encouraged). Inside Yellowstone National Park, seasons, limits, and tackle rules are different (barbless, fly- or lure-only, August opener, cutthroat catch-and-release, etc.). See the park’s current fishing regulations.