Big Thompson River Fishing Regulations
Larimer County, Colorado · 2026 size limits, bag limits, and seasons
Big Thompson River is a river in Larimer County, Colorado. It has its own fishing regulations for 7 species, including Brook Trout, Brown Trout, Cutthroat Trout, and Golden Trout. These rules replace Colorado's statewide limits on this water.
Map of Big Thompson River
Fish with special rules on Big Thompson River
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Big Thompson River limits by species (2026)
| Species | Size limit | Daily bag | Season |
|---|---|---|---|
| All Fish SpeciesArtificial Only | – | – | Always open |
 Brook Trout | – | Catch & release only | Year-round |
 Brown Trout | – | Catch & release only | Year-round |
 Cutthroat Trout | – | Catch & release only | Year-round |
 Golden Trout | – | Catch & release only | Year-round |
 Lake Trout | – | Catch & release only | Year-round |
 Rainbow Trout | – | Catch & release only | Year-round |
 Steelhead | – | Catch & release only | Year-round |
– means no limit is listed for this water. Rules not shown here follow Colorado's statewide regulations.
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Big Thompson River fishing: common questions
What fish have special regulations on Big Thompson River?
7 species have rules specific to Big Thompson River: Brook Trout, Brown Trout, Cutthroat Trout, Golden Trout, Lake Trout, Rainbow Trout, and Steelhead.
What is the brook trout limit on Big Thompson River?
Brook Trout are catch and release only on Big Thompson River.
What is the brown trout limit on Big Thompson River?
Brown Trout are catch and release only on Big Thompson River.
What is the cutthroat trout limit on Big Thompson River?
Cutthroat Trout are catch and release only on Big Thompson River.
Is Big Thompson River catch and release?
Some rules on Big Thompson River are catch and release only, covering Brook Trout, Brown Trout, Cutthroat Trout, Golden Trout, and Lake Trout and others. Check the table for the section and dates that apply.
Do Colorado statewide fishing rules apply on Big Thompson River?
Where Big Thompson River has its own rule for a species, that rule replaces the statewide limit. For species not listed on this page, Colorado's statewide regulations apply. Regulations are set by the Colorado Parks and Wildlife; confirm with the official 2026 regulations before keeping a fish.
Other Colorado waters with special regulations
- South Platte River
- Yampa River
- Colorado River
- White River
- Poudre River · Larimer
- Gunnison River
- Blue River · Grand, Summit
- Roaring Fork River
- Arkansas River · Chaffee , Lake , Fremont , Pueblo
- Animas River · La Plata
- Eagle River · Eagle
- Taylor River
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