2018 Illinois House of Representatives election
| 
 | ||||||||||||||||||||||||||||||||||
| All 118 seats in the Illinois House of Representatives 60 seats needed for a majority | ||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 
 | ||||||||||||||||||||||||||||||||||
| Results: Democratic gain Republican gain Democratic hold Republican hold Vote share: 50–60% 60–70% 70–80% >90% 50–60% 60–70% 70–80% >90% | ||||||||||||||||||||||||||||||||||
| 
 | ||||||||||||||||||||||||||||||||||
| Elections in Illinois | 
|---|
The 2018 elections for the Illinois House of Representatives took place on Tuesday, November 6, 2018, to elect representatives from all 118 districts. The winners of this election served in the 101st General Assembly, with seats apportioned among the states based on the 2010 United States census. The Democratic Party had held a House majority since 1997. The inauguration of the 101st General Assembly occurred on Wednesday, January 9, 2019. The Democrats flipped eight seats, while Republicans flipped one seat, resulting in a net gain of seven seats for the Democratic caucus.
The elections for Illinois's 18 congressional districts, governor and lieutenant governor, statewide constitutional officers, and the Illinois Senate were also held on this date.