Minnesota · Grant County
Thompson Lake Fishing guide
Thompson Lake sits in Grant County, Minnesota, and covers 154 acres, reaching 22 ft at its deepest point. Average water clarity runs about 8.4 ft. The Minnesota DNR has surveyed the lake 9 times, most recently in 2023, with walleye, largemouth bass, northern pike and bluegill in the nets.
DNR survey data
Fish species
WalleyeLast stocked 2025Excellent numbers9per gill net21"Typical26"Biggest
Lengths measured · 42 fish
Recent · 2021 + 2023Lengths measured · 15 fish
2023Lengths measured · 27 fish
2021Lengths measured · 43 fish
2015Lengths measured · 38 fish
2009Largemouth bassGood numbers59.3per hr (electrofishing)13"Typical19"Biggest
Lengths measured · 211 fish
Recent · 2021 + 2023Lengths measured · 39 fish
2023Lengths measured · 172 fish
2021Lengths measured · 206 fish
2015Lengths measured · 44 fish
2009No recent survey rating.
BluegillJust a few4.7per trap net5"Typical8"Biggest
Lengths measured · 58 fish
Recent · 2021 + 2023Lengths measured · 13 fish
2023Lengths measured · 45 fish
2021Lengths measured · 31 fish
2015Lengths measured · 121 fish
2009CrappieJust a few2.7per trap net5"Typical12"Biggest
Lengths measured · 39 fish
Recent · 2021 + 2023Lengths measured · 9 fish
2023Only 9 fish measured that year — too few to read as a shape.
Lengths measured · 30 fish
2021Lengths measured · 16 fish
2015Lengths measured · 5 fish
2009Only 5 fish measured that year — too few to read as a shape.
No recent survey rating.
Rates come from standard DNR survey gear (gill nets, trap nets, electrofishing), judged against statewide benchmarks for the same gear, so the same number of fish per net can read differently for two species. Where the standard gear can't count a species reliably, only presence and size are listed. Typical is the middle fish of those measured. Open a row for the full length spread, survey by survey.
How to fish Thompson Lake through the year
Walleye
- Spring
- Walleye are shallow, on and just off the spawning flats and the first green weeds.
- Early summer
- Walleye are setting up on the outside weed edge, points and shallow structure.
- Summer
- Walleye are working the weed edge, points and any wind-blown structure.
- Fall
- Walleye are packing onto the sharpest breaks and points as the water cools, in big schools with short windows.
Largemouth bass
- Spring
- Largemouth are moving up into the warming bays and flats, staging around wood, docks and new weeds to spawn.
- Early summer
- Largemouth are on the shallow spawning flats and protected bays, where beds go on firm bottom next to isolated cover.
- Summer
- Largemouth are in and along the weeds: cabbage and milfoil edges, matted cover and shade.
- Fall
- Largemouth are chasing bait back onto the flats and into the remaining green weeds, feeding hard and shallow before the freeze.
Season patterns for each species. Open the live map for today's wind, light and water temp.
Size history
Biggest fish by survey year
| Survey year | Walleye | Largemouth bass | Bluegill |
|---|---|---|---|
| 2023 | 26" | 19" | 8" |
| 2021 | 26" | 18" | 6" |
| 2015 | 26" | 19" | 9" |
| 2009 | 27" | 18" | 12" |
| 2004 | 24" | 16" | 7" |
| 1999 | 25" | 15" | 8" |
| 1994 | 8" | — | 8" |
Longest fish measured by DNR survey crews in each year's nets. Survey gear samples the population, so the lake usually holds larger fish than any survey measured.
Suggested tackle
What to bring
Top presentations for this lake's structure and clarity:
Walleye · Trolling
Snap Weights + Stickbaits
4–5" suspending or slow-floating stickbait
Largemouth bass · Soft plastics
Texas-Rigged Worm
7" ribbon-tail or straight-tail plastic worm
Largemouth bass · Soft plastics
Free Rig
Creature bait or magnum finesse worm
Bluegill · Live bait
Clip-On Bobber + Worm
half to whole garden nightcrawler
Bluegill · Soft plastics
Tungsten Jig + Micro Plastic
1–1.5" micro plastic
Full setups, including hooks, weights and line, are on the live map. As an Amazon Associate I earn from qualifying purchases.
DNR stocking records
Stocking history
| Year | Species | Stocked |
|---|---|---|
| 2025 | Walleye | 37,000 fry |
| 2023 | Walleye | 74,000 fry |
| 2021 | Walleye | 74,000 fry |
| 2019 | Walleye | 74,000 fry |
| 2017 | Walleye | 74,000 fry |
MN DNR · in their words
From the 2023 survey
This targeted survey was completed to determine extent of winterkill following the severe 2022-2023 winter. Trap netting results suggested that winterkill severity was low and restorative stockings were not warranted. Gamefish species present included Black Crappie, Bluegill, Largemouth Bass, and Walleye. The majority of fish collected for these species were larger individuals.
Narrative text from the Minnesota DNR lake survey.
Recent reports
Thompson Lake fishing reports
Recent reports on Thompson Lake from guides, tournaments and regular anglers. Anything posted in the last two weeks also bumps the matching spots on the live map, so you'll see a "matches a recent report" tag on them.
Public water access
Getting on the water
- Thompson Lake (trailer launch)
DNR bathymetry
Thompson Lake depth map
Within 30 miles
Nearby lakes
- Elk Lake · 207 ac · 2.7 mi
- Barrett Lake · 530 ac · 3.6 mi
- Lower Elk Lake · 131 ac · 3.7 mi
- Red Rock Lake · 904 ac · 6.1 mi
- Long Lake · 202 ac · 6.9 mi
- Pomme de Terre Lake · 1,816 ac · 8.3 mi
- Stowe Lake · 377 ac · 10.5 mi
- Pelican Lake · 3,761 ac · 10.5 mi
Quick answers
Frequently asked questions
How deep is Thompson Lake?
Thompson Lake reaches 22 ft at its deepest point with a mean depth of 16 ft; about 48% of the lake is littoral (15 ft or shallower).
How big is Thompson Lake?
Thompson Lake covers 154 acres with about 2.4 miles of shoreline.
How clear is the water in Thompson Lake?
DNR Secchi readings on Thompson Lake average 8.4 ft of visibility, middling clarity for a Minnesota lake.
What fish are in Thompson Lake?
Minnesota DNR surveys (most recently 2023) record walleye, largemouth bass, northern pike, bluegill, crappie, yellow perch.
Is Thompson Lake stocked?
Yes. The DNR stocked walleye in 2025; the stocking table on this page lists every year back to 2017.
Does Thompson Lake have a public access?
Yes. Thompson Lake has one public access site: Thompson Lake (trailer launch).
How big do walleye get in Thompson Lake?
The biggest walleye measured in recent DNR surveys taped 26"; the size-history table on this page tracks the biggest fish in each survey back to 1994.
When was Thompson Lake last surveyed?
The Minnesota DNR last surveyed Thompson Lake in 2023, the most recent of 9 surveys on record.
Page updated .
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