Check which species have trophy potential in Old Altamont Reservoir
Old Altamont Reservoir fishing reports
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When are Largemouth Bass biting on Old Altamont Reservoir?
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Fishing regulations at Old Altamont Reservoir, IL
Disclaimer: Always check local fishing regulations, water access rights and land ownership before fishing, regardless of any catches logged in that area by the Fishbrain community. Fishbrain has mapped millions of acres of government-owned land across the USA to help you identify potential fishing access, but you are responsible for ensuring compliance with all legal requirements.
Fishing regulations in Illinois can change throughout the year. Make sure to check this page before fishing for the most up to date rules and regulations for the current season. Local regulations govern when you can fish, the max size of the fish you can keep, how many fish you can keep, and more.
Below you will see fishing regulations for catching Largemouth bass as of May 4th, 2026. To view regulations for a different fish species, please click on your preferred species in the drop-down.
Seasons
Bag limit
Aggregate
There is no statewide size limit. Daily harvest limit is 6 Bass, either singly or in the aggregate, except as specified under Site-Specific Regulations. Only statewide regulations are shown herein, but you can access Site-Specific Regulations online.
Micropterus nigricans
Regulations for
FAQ about Old Altamont Reservoir fishing
- Largemouth bass - 1 members reported to have caught this fish
- @mandypontious-durbin reported a nice Largemouth bass.
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