Montana Fly Fishing Hatch Chart
Interactive fly fishing hatch chart for Montana. See which mayflies, caddisflies, stoneflies, and midges are hatching each month and get fly pattern recommendations. Based on 10 years of scientific observation data (2015–2024).
Using the Montana hatch chart
This statewide chart compares when aquatic insect observations have been recorded in Montana. Select a month to compare the share of annual mayfly, caddisfly, stonefly, and midge observations, then review fly patterns commonly used to imitate those insect groups.
Our Montana hatch chart is built from 10 years of scientific observation data (2015–2024), covering the major aquatic insect orders: Ephemeroptera (mayflies), Trichoptera (caddisflies), Plecoptera (stoneflies), and Diptera (midges). Use it to plan your fishing trips around the most productive emergence windows of the season. Actual timing varies with elevation, latitude, water temperature, and seasonal weather, so confirm current activity with local reports and on-water observation.
Montana river guides
- Madison River — The Madison River is a classic Montana trout destination, extending from high-elevation water near West Yellowstone through broad valley and tailwater reaches.
- Gallatin River — The Gallatin River is a varied Montana trout river with mapped reaches from canyon water through the valley. Its gauges help separate local conditions from broader regional weather.
- Yellowstone River — The Yellowstone is a large Montana river where current, seasonal runoff, and access logistics shape the fishing day. Use the gauges to understand the river before choosing a section.
- Rock Creek — Montana's Rock Creek is a smaller, scenic trout river with abundant mapped water. Its many tributary and fork names make a map check useful when planning a specific access point.