| Election Name: | 2016 Illinois Senate elections |
| Country: | Illinois |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2014 Illinois Senate election |
| Previous Year: | 2014 |
| Next Election: | 2018 Illinois Senate election |
| Next Year: | 2018 |
| Seats For Election: | 40 of 59 seats in the Illinois Senate |
| Majority Seats: | 30 |
| Leader1: | John Cullerton |
| Party1: | Democratic Party (United States) |
| Leaders Seat1: | 6th-Chicago |
| Last Election1: | 39 |
| Seats1: | 37 |
| Seat Change1: | 2 |
| Popular Vote1: | 1,906,007 |
| Percentage1: | 59.45% |
| Swing1: | 13.90% |
| Leader2: | Christine Radogno |
| Party2: | Republican Party (United States) |
| Leaders Seat2: | 41st-La Grange |
| Last Election2: | 20 |
| Seats2: | 22 |
| Seat Change2: | 2 |
| Popular Vote2: | 1,299,861 |
| Percentage2: | 40.55% |
| Swing2: | 13.90% |
| President | |
| Posttitle: | President-Elect |
| Before Election: | John Cullerton |
| Before Party: | Democratic Party (United States) |
| After Election: | John Cullerton |
| After Party: | Democratic Party (United States) |
The Illinois State Senate Election of 2016 determined, along with 19 senators not up for re-election, the membership of the 100th Illinois State Senate. The Democratic Party retained its majority, losing two seats - the 47th district in Western Illinois, and the 59th in the State's South - which were both won by Republicans.
| Illinois State Senate Elections, 2016 | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | % change | Previous Senate | Candidates | Elected | Total seats | +/– | ||||
| Seats held over | Seats up | Total Seats before election | ||||||||||
| Democratic | 1,906,007 | 59.45% | 13.90% | 11 | 28 | 39 | 32 | 26 | 37 | 2 | ||
| Republican | 1,299,861 | 40.55% | 13.90% | 8 | 12 | 20 | 21 | 14 | 22 | 2 | ||
| Write-Ins | 125 | 0.00% | N/A | 0 | 0 | 0 | 2 | 0 | 0 | 0 | ||
| Totals | 1,045,787 | 100.00% | N/A | 19 | 40 | 59 | 26 | 19 | 59 | — | ||
| align=center | District 1 • District 2 • District 4 • District 5 • District 7 • District 8 • District 10 • District 11 • District 13 • District 14 • District 16 • District 17 • District 19 • District 20 • District 22 • District 23 • District 25 • District 26 • District 28 • District 29 • District 31 • District 32 • District 34 • District 35 • District 37 • District 38 • District 40 • District 41 • District 43 • District 44 • District 46 • District 47 • District 49 • District 50 • District 52 • District 53 • District 55 • District 56 • District 58 • District 59 |