The 40th District of the Iowa Senate is located in eastern Iowa, and is currently composed of part of Linn County.
Ken Rozenboom is the senator currently representing the 40th District.
The area of the 40th District contains two Iowa House of Representatives districts:
The district is also located in Iowa's 2nd congressional district, which is represented by Mariannette Miller-Meeks.
The district has previously been represented by: