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1,606-acre lake in Simcoe County, Ontario. The lake tops out around 20 ft. The depth chart comes from Ontario Ministry of Natural Resources and Forestry bathymetric survey data, so the contours are survey-derived rather than computer-modeled. The depth data here comes from the Ontario MNRF survey of 1968, a decades-old survey (a transect sounding survey). The season-by-season read for each species follows, from the map's own numbers.
Drawn out, this is 1,613 acres of water rimmed by 11.6 miles of bank — 10 islands included. Index 2.1 on the shoreline: a few honest points and pockets, nothing labyrinthine. About 68% of the surface sits shallower than 15 ft — that's the weed-and-bait zone. Tip to tip the water measures near 2.3 mi with a 2.1-mi widest point. The water lies in Simcoe County. Closest neighbour on DepthScout: Mud Lake, 2 mi southeast of here.
These fish are listed in an exact-water agency record as forage or ecological context. They are not target-species profiles and do not affect DepthScout's Prime, Good, or Fair spot ratings.
Official Ontario MNRF Fish ON-Line record. The listing documents source-recorded presence, not present abundance or guaranteed catchability.
Early season walleye use the shallows, holding in 4 to 15 ft. Summer is a 6 to 20 ft game here, winter a 6 to 20 ft one. The chart's best answer is Break off the point — drop-off, 8 ft, prime for fall. Best bite is the evening and early morning. Tie on a crawler harness on bottom bouncer or a deep crankbait (trolled) and you're in the game.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Break off the point (8 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 20 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (8 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 20 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (8 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 20 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (20 ft) | Jigging spoon + minnow head, Rattle bait |
Spring yellow perch on Lake St. John hold shallow, usually 3 to 12 ft. By summer they slide out to 6 to 20 ft, and by winter most fish are in 6 to 20 ft. The chart's best answer is Deep basin — deep basin, 20 ft, prime for fall. Prime time lands in early morning. The summer box starts with a drop-shot micro plastics or a small spoon tipped with worm.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (1 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (20 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 6 to 20 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (20 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (20 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring puts northern pike in skinny water — 2 to 8 ft is the zone. As the season builds they drop to 8 to 20 ft, wintering in 5 to 15 ft. Fall northern pike concentrate at Break off the point, a prime-rated drop-off around 8 ft. Warm-month bites cluster around early morning and the evening. A bucktail or a weedless spoon over cabbage covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (1 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (8 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (8 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Break off the point (8 ft) | Tip-ups, Large jigging spoon |
The spring pattern is a shallow one: muskellunge in 3 to 12 ft. As the season builds they drop to 6 to 20 ft, wintering in 6 to 20 ft. Top water on the chart: Break off the point, a drop-off in the 8 ft range, prime in fall. Time it for the evening and early morning. Summer baits: a double-10 bucktail or a topwater (walk-the-dog / creeper) gets it done.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dusk | Shallow bay flat (1 ft) | Smaller bucktail (#8 blades), 6" glide bait |
| Summer | 6 to 20 ft chart-limited; documented 8 to 25 ft | dusk & dawn | Break off the point (8 ft) | Double-10 bucktail, Topwater (walk-the-dog / creeper) |
| Fall | 5 to 20 ft chart-limited; documented 8 to 30 ft | midday & dusk | Break off the point (8 ft) | Big rubber (Bull Dawg style), 10"+ glide bait |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday | Deep basin (20 ft) | Large rubber, crawled slow |
Spring puts smallmouth bass in skinny water — 3 to 12 ft is the zone. As the season builds they drop to 6 to 20 ft, wintering in 6 to 20 ft. Winter smallmouth bass concentrate at Break off the point, a prime-rated drop-off around 8 ft. Warm-month bites cluster around early morning and the evening. A drop shot (goby/minnow) or a ned rig covers the summer program.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (1 ft) | Ned rig, Tube jig |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Break off the point (8 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 6 to 20 ft chart-limited; documented 8 to 25 ft | midday & dawn | Break off the point (8 ft) | Jerkbait, Blade bait |
| Winter | 6 to 20 ft chart-limited; documented 20 to 45 ft | midday | Break off the point (8 ft) | Blade bait, Hair jig |
In spring, largemouth bass run shallow here, mostly 2 to 10 ft. Summer pushes them deeper, 8 to 20 ft, and winter fish settle into 6 to 20 ft. Break off the point is the standout, a drop-off at roughly 8 ft, rated prime for winter largemouth bass. Time it for early morning and the evening. You won't need more than a texas-rigged 10" worm or a deep-diving crankbait most summer days.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (1 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (8 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (1 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday | Break off the point (8 ft) | Blade bait, Jigging spoon |
Lake St. John also holds rock bass (5 to 20 ft in summer), crappie (6 to 20 ft in summer), bluegill (4 to 15 ft in summer), pumpkinseed (2 to 10 ft in summer), brown bullhead (3 to 12 ft in summer), channel catfish (6 to 20 ft in summer), common carp (3 to 15 ft in summer), bowfin (2 to 14 ft in summer), grass pickerel (1 to 9 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Lake St. John carries 7 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 20 ft down.
Access data: Geospatial Ontario - Fishing Access Points; Government of Ontario - MNR Unpatented Crown Land Shoreline; Government of Ontario - MNR Unpatented Crown Land Shoreline. Confirm conditions and fees locally before you launch.
Season dates, license requirements, and size and bag limits for Ontario waters are set by the Ontario fishing regulations (FMZ summary) — and special regulations can apply to Lake St. John specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Lake St. John is about 20 ft (6 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1968, a decades-old survey (a transect sounding survey).
Anglers target walleye, yellow perch, northern pike, muskellunge, smallmouth bass, largemouth bass, rock bass, crappie, bluegill, pumpkinseed, brown bullhead, channel catfish, common carp, bowfin, grass pickerel on Lake St. John.
Break off the point is the top-rated area: a drop-off in about 8 ft of water that rates prime for walleye in fall. Scroll up to the map for the complete spot list by species and season.
For walleye, the summer bite is best in the evening and early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Lake St. John is regulated by the Ontario fishing regulations (FMZ summary). Check the official Ontario regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Mud Lake 2 mi · Lake Couchiching 3 mi · Grass Lake 6 mi · Buck Lake 8 mi · Young Lake 8 mi · Beaver Lake 9 mi · Sparrow Lake 9 mi · Clearwater Lake 9 mi · Long Lake 11 mi · Dalrymple Lake 11 mi · Bass Lake 11 mi · Eastern L. 11 mi
See how Lake St. John stacks up: best largemouth bass lakes in Ontario · best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best northern pike lakes in Ontario
More water nearby: Simcoe County fishing maps (31 charts). Browse all Ontario fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.