Pennington County Flag

Pennington County

State:
South Dakota
County Seat:
Rapid City

Pennington County's estimated 2026 population is 117,272 with a growth rate of 0.41% in the past year according to the most recent United States census data. Pennington County is the 2nd largest county in South Dakota. The 2010 population was 101,253 and has seen a growth of 15.82% since that time.

117,272
Total Population
42
Population Density (mi²)
2
Population Rank (State)
480 0.41%
Annual Population Growth

Pennington County Population

Demographics

Economics and Income Statistics