COUNTY · SD

Day County, South Dakota

Day County is a county in South Dakota with FIPS code 46037 and an estimated population of 5,451 (Census 2023), 32nd largest of 66 in the state.

County facts

Name
Day County
State
South Dakota
Type
county
FIPS code
46037
State FIPS
46
Population (2023)
5,451
Change since 2020
+0.1%
State rank
32 of 66

Population is the Census Bureau’s Vintage 2023 estimate.

Other counties in South Dakota

Questions

What is the FIPS code for Day County?

Day County, South Dakota has the five-digit FIPS code 46037: 46 for the state and 037 for the county.

What state is Day County in?

Day County is in South Dakota.

How do I know if an address is in this county?

Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.

Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.