Asking what county Lake Tahoe is in, is actually a trick question.
The reason: Lake Tahoe is in four different counties across two states.
The counties are:
El Dorado County, California
Placer County, California
Washoe County, Nevada
Douglas County, Nevada
Because the two California counties are generally less mountainous near the shoreline, those counties contain the majority of Tahoe region homes and businesses.
Here are polygons for the four counties represented on a Google My Map:
As you can see from the map, South Lake Tahoe is in El Dorado County, Tahoe City is in Placer County, and Incline Village is in Washoe County.
The Fifth Polygon - Carson City
There's some confusion as to whether Carson City is both a city and a county, as is San Francisco.
While Carson City, NV is treated as a county-equivalent for census purposes, it is not a county. Officially, it is the Consolidated Municipality of Carson City.
Before 1969, Carson City was the county seat of Ormsby County. In 1969, Ormsby County was abolished. The former county's territory was merged with Carson City.
Lake Tahoe's Elbow
The elbow in the geographic center of the lake, where the California/Nevada state line makes an abrupt turn, is at almost exactly 39°N and 120°W. The connecting counties at this confluence are El Dorado and Douglas counties.
While different counties have different permitting procedures and even different tax rates, they all have excellent access to the natural beauty and many activities associated with Lake Tahoe.
