It includes the cities of Fitchburg, Fort Atkinson, Lake Mills, Stoughton, Sun Prairie, and Waterloo, and the villages of Cottage Grove, Deerfield, and Marshall, and parts of the city of Madison and the village of McFarland.

[2] Melissa Ratcliff is the senator representing the 16th district.

Before serving as senator, she served in the Wisconsin State Assembly from 2023 to 2025, representing Sun Prairie and Madison's far east side.

The portion of the district in Dodge and Jefferson counties fall within Wisconsin's 5th congressional district, which is represented by U.S. Representative Scott L. Fitzgerald.

The remainder of the district, in Dane County, falls within Wisconsin's 2nd congressional district, represented by U.S. Representative Mark Pocan.