Flathead Lake is about 2.4 times bigger than Lake of the Ozarks.

Lake of the Ozarks is approximately 212 km² (82 sq mi), while Flathead Lake is approximately 510 km² (197 sq mi), making Flathead Lake 141% larger than Lake of the Ozarks.
Tip: This to-scale comparison of Lake of the Ozarks vs. Flathead Lake uses the Mercator projection, which distorts the size of regions near the poles.
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