Sanilac County, Michigan

Sanilac County, Michigan
Sanilac County Courthouse
Location within the U.S. state of Michigan
Coordinates: 43°28′N 82°38′W / 43.46°N 82.64°W / 43.46; -82.64
Country United States
State Michigan
FoundedSeptember 10, 1822 (created)
December 31, 1849 (organized)
SeatSandusky
Largest citySandusky
Area
 • Total
1,590 sq mi (4,100 km2)
 • Land963 sq mi (2,490 km2)
 • Water627 sq mi (1,620 km2)  39%
Population
 (2020)
 • Total
40,611
 • Estimate 
(2024)
40,293
 • Density41.8/sq mi (16.1/km2)
Time zoneUTC−5 (Eastern)
 • Summer (DST)UTC−4 (EDT)
Congressional district9th
Websitesanilaccounty.net

Sanilac County (/sænəlæk/ SAN-ə-lack) is a county located in the Thumb region of the U.S. state of Michigan. As of the 2020 Census, the population was 40,611. The county seat is Sandusky. The county was created on September 10, 1822, and was fully organized on December 31, 1849. Sanilac County is considered to be part of the Thumb of Michigan, a subregion of the Flint/Tri-Cities. Sanilac County enjoys seasonal tourism in towns such as Lexington, Port Sanilac, and Carsonville. Sanilac County is economically attached to St. Clair County and Huron County and is largely composed of nearly flat areas of rich soil.