Cutthroat Trout Stocked · 29 plants · last June 2026 Last stocked June 2026 · avg 5.8 in · 29 plants
Cutthroat Trout species guideGrassy Lake Reservoir fishing
Grassy Lake Reservoir fishing is stocked with Cutthroat Trout on a reservoir. Also recorded: Rainbow trout and Lake trout. It is stocked about once a year since 1997, most often in June and July. Species guides list dawn and dusk for Rainbow trout and dawn for Lake trout.
- Last stocked
- June 2026
- Cutthroat Trout
- Plants on record
- 29
- Since 1997
- Species stocked
- 1 (+2 also recorded)
- Average size
- 5.8 in
- Elevation
- 7,201 ft
Fish at Grassy Lake Reservoir
Cutthroat Trout Stocked · 29 plants · last June 2026 
Rainbow trout Confirmed present Best: dawn, dusk Best: dawn, dusk
Rainbow trout species guide
Lake trout Confirmed present Best: dawn Best: dawn
Lake trout species guideGrassy Lake Reservoir, a 1,477-acre reservoir, is located near the Wyoming-Idaho border between Yellowstone and Grand Teton National Parks. Popular activities at Grassy Lake include fishing. Anglers can find fish species such as rainbow, cutthroat, and lake trout in this reservoir. (recreation.gov, accessed September 22, 2026)
Drafted by AI from the cited sources and checked before publishing.
How Grassy Lake Reservoir is stocked
No plants recorded in 1999 and 2000.
Fish stocked in 1997
15,746
Fish stocked in 1998
16,803
Fish stocked in 2001
16,534
Fish stocked in 2002
16,179
Fish stocked in 2003
14,808
Fish stocked in 2004
15,652
Fish stocked in 2005
15,184
Fish stocked in 2006
15,168
Fish stocked in 2007
15,228
Fish stocked in 2008
14,406
Fish stocked in 2009
17,325
Fish stocked in 2010
5,229
Fish stocked in 2011
12,276
Fish stocked in 2012
7,875
Fish stocked in 2013
14,994
Fish stocked in 2014
11,916
Fish stocked in 2015
13,500
Fish stocked in 2016
15,265
Fish stocked in 2017
16,092
Fish stocked in 2018
16,342
Fish stocked in 2019
14,448
Fish stocked in 2020
15,017
Fish stocked in 2021
15,872
Fish stocked in 2022
15,020
Fish stocked in 2023
16,296
Fish stocked in 2024
16,495
Fish stocked in 2025
16,054
Fish stocked in 2026
15,009
Stocking history
| Date | Species | Quantity | Avg. length | Source |
|---|---|---|---|---|
| June 2026 | Cutthroat Trout | 15,009 | 5.2 in | report |
| June 2025 | Cutthroat Trout | 16,054 | 5.5 in | report |
| June 2024 | Cutthroat Trout | 16,495 | 5.5 in | report |
| July 2023 | Cutthroat Trout | 16,296 | 5.8 in | report |
| July 2022 | Cutthroat Trout | 15,020 | 5.2 in | report |
| July 2021 | Cutthroat Trout | 15,872 | 5.6 in | report |
| July 2020 | Cutthroat Trout | 15,017 | 5.9 in | report |
| July 2019 | Cutthroat Trout | 14,448 | 5.1 in | report |
| July 2018 | Cutthroat Trout | 16,342 | 5.2 in | report |
| July 2017 | Cutthroat Trout | 16,092 | 4.7 in | report |
| July 2016 | Cutthroat Trout | 15,265 | 5.1 in | report |
| June 2015 | Cutthroat Trout | 13,500 | 4.6 in | report |
| July 2014 | Cutthroat Trout | 4,356 | 4.3 in | report |
| June 2014 | Cutthroat Trout | 7,560 | 4.3 in | report |
| July 2013 | Cutthroat Trout | 14,994 | 5.4 in | report |
| July 2012 | Cutthroat Trout | 7,875 | 5.5 in | report |
| July 2011 | Cutthroat Trout | 12,276 | 7.4 in | report |
| July 2010 | Cutthroat Trout | 5,229 | 6.8 in | report |
| July 2009 | Cutthroat Trout | 17,325 | 6.4 in | report |
| August 2008 | Cutthroat Trout | 14,406 | 7 in | report |
| June 2007 | Cutthroat Trout | 15,228 | 6.8 in | report |
| July 2006 | Cutthroat Trout | 15,168 | 6.4 in | report |
| July 2005 | Cutthroat Trout | 15,184 | 5.6 in | report |
| July 2004 | Cutthroat Trout | 15,652 | 7.4 in | report |
| July 2003 | Cutthroat Trout | 14,808 | 6.1 in | report |
| July 2002 | Cutthroat Trout | 16,179 | 7.1 in | report |
| June 2001 | Cutthroat Trout | 16,534 | 7.4 in | report |
| July 1998 | Cutthroat Trout | 16,803 | 5.4 in | report |
| August 1997 | Cutthroat Trout | 15,746 | 6.4 in | report |
Access and facts
- Water type
- reservoir
Bureau of Reclamation reservoir on Grassy Lake Road (Forest Service Road 135), the 36-mile gravel road from Flagg Ranch, between Yellowstone and Grand Teton, to Ashton, Idaho. High clearance advised; not plowed in winter. No facilities at the lake; NPS has 14 free primitive campsites along the road.
Drafted by AI from the cited sources and checked before publishing.
Advisories, closures, regulations and water conditions change. Check the Wyoming Game and Fish Department before you go.
About Grassy Lake Reservoir
There are no improvements, services, or facilities at Grassy Lake. (recreation.gov, accessed September 22, 2026)
Drafted by AI from the cited sources and checked before publishing.
Nearest lakes
Public land at Grassy Lake Reservoir
Grassy Lake Reservoir is inside Caribou-Targhee National Forest.
It is 0.4 miles outside the edge of Yellowstone National Park.
It is 0.8 miles outside the edge of Jedediah Smith Wilderness.
Boundaries from Public Lands DB, part of the same network.
Common questions
What fish are at Grassy Lake Reservoir?
Fishing Grassy Lake Reservoir usually means Cutthroat Trout. All 29 plants on record are Cutthroat Trout. Cutthroat Trout was last stocked June 2026, averaging 5.8 in. Rainbow trout and Lake trout are recorded here outside the stocking reports.
When is Grassy Lake Reservoir stocked?
Last stocked June 2026. It is stocked about once a year since 1997, most often in June and July. No plants recorded in 1999 and 2000.
How big are the fish stocked at Grassy Lake Reservoir?
Cutthroat Trout stocked at Grassy Lake Reservoir average 5.8 in.
How do you get on Grassy Lake Reservoir?
Bureau of Reclamation reservoir on Grassy Lake Road (Forest Service Road 135), the 36-mile gravel road from Flagg Ranch, between Yellowstone and Grand Teton, to Ashton, Idaho. High clearance advised; not plowed in winter. No facilities at the lake; NPS has 14 free primitive campsites along the road.
Which lakes near Grassy Lake Reservoir were stocked more recently?
Fish Lake (6.4 mi) was stocked more recently. Fish Lake is also stocked with Cutthroat Trout.