Chicago Municipal Elections: Schedules, Candidates, and Voting
Chicago municipal elections determine who holds the city's executive offices, legislative seats, and a range of independent positions that shape daily governance. This page covers how those elections are structured, when they occur, who can appear on the ballot, and what distinguishes a consolidated primary from a runoff — with specific attention to the rules that apply to Chicago under Illinois state law and the city's home rule framework.
Definition and scope
Chicago municipal elections are elections conducted within the corporate limits of the City of Chicago to fill offices created by state statute or city ordinance. The principal offices subject to municipal election include the Mayor, City Clerk, City Treasurer, and the 50 alderpersons (officially "aldermen and alderwomen") who comprise the Chicago City Council. Each of the 50 Chicago aldermanic wards elects one representative.
Chicago municipal elections are governed by the Illinois Municipal Code (65 ILCS 5) and the Illinois Election Code (10 ILCS 5), with administrative oversight provided by the Chicago Board of Election Commissioners, an independent body created under Illinois statute.
Scope limitations: This page addresses city-level offices only. Elections for Cook County offices — including the Cook County Board of Commissioners and Cook County Assessor — are not covered here. Illinois General Assembly races, U.S. Congressional contests, and Chicago Public Schools board elections operate under separate schedules and filing requirements and fall outside this page's coverage. Voters residing in Chicago but adjacent to unincorporated Cook County areas should consult the Cook County Clerk for races that extend beyond city boundaries.
How it works
Chicago municipal elections follow a two-stage structure defined by state law: a Consolidated Primary held on the last Tuesday in February of the applicable year, followed, if necessary, by a Consolidated Election (the general) on the first Tuesday in April.
The cycle proceeds as follows:
- Petition filing window — Candidates collect signatures on nominating petitions during a 90-day window that closes approximately 141 days before the primary. The required signature threshold for Mayor is 12,500 valid signatures; for aldermanic candidates, it is 473 signatures (these figures are set by the Illinois Election Code and verified by the Chicago Board of Election Commissioners).
- Objection period — After petitions are filed, any registered voter may file a written objection. The Electoral Board — composed of the Mayor, City Clerk, and City Treasurer — hears objections to aldermanic candidates; objections to citywide candidates are heard by a separate Electoral Board constituted under 10 ILCS 5/10-9.
- Consolidated Primary (February) — All candidates who qualify appear on the primary ballot. If any candidate for a citywide office receives more than 50 percent of the valid votes cast, that candidate wins outright and no runoff occurs.
- Runoff / Consolidated Election (April) — If no candidate clears 50 percent in February, the top two vote-getters advance to the April election. Aldermanic races follow the same majority-threshold rule.
Chicago uses a nonpartisan structure for municipal races: no party label appears on the municipal ballot, and all registered voters may participate regardless of party affiliation. This contrasts with Illinois partisan primaries for state and federal offices, where voters select a party ballot.
Early voting opens no fewer than 40 days before each election (10 ILCS 5/19A-15), and vote-by-mail ballots are available to any registered voter upon request under the Illinois Vote by Mail statute.
Common scenarios
Incumbent runs unopposed: If only one candidate files valid petitions for an office, that candidate appears on the April ballot without a February primary. The Chicago City Clerk certifies the result.
No candidate reaches 50 percent in February: The most common scenario in contested mayoral races. In the 2019 mayoral primary, 14 candidates appeared on the ballot; no one reached 50 percent, sending Lori Lightfoot and Toni Preckwinkle to an April runoff (Chicago Board of Election Commissioners, 2019 primary results).
Aldermanic vacancy mid-term: When an aldermanic seat becomes vacant outside an election cycle, the Mayor appoints a replacement under 65 ILCS 5/3.1-10-50. That appointee serves until the next regularly scheduled municipal election at which the seat appears.
Write-in candidacy: Illinois law permits write-in votes for municipal offices, but a write-in candidate must file a declaration of intent with the Chicago Board of Election Commissioners at least 61 days before the election to have write-in votes counted (10 ILCS 5/17-16.1).
Special service area and school board elections: These are separate administrative elections not conducted on the February/April consolidated calendar and are not covered here.
Decision boundaries
Understanding which election rules apply depends on the type of office:
| Office | Ballot type | Majority threshold | Term length |
|---|---|---|---|
| Mayor | Nonpartisan | >50% to win in primary | 4 years |
| City Clerk | Nonpartisan | >50% to win in primary | 4 years |
| City Treasurer | Nonpartisan | >50% to win in primary | 4 years |
| Alderperson (50 wards) | Nonpartisan | >50% to win in primary | 4 years |
All four citywide offices — Mayor, City Clerk, City Treasurer, and the 50 aldermanic seats — are elected on the same four-year cycle. Chicago does not use staggered terms for the City Council, meaning all 50 wards are on the ballot simultaneously every four years.
The Chicago Mayor's Office and Chicago City Treasurer pages provide additional context on the roles these officials perform once elected.
Residency is a hard eligibility requirement: aldermanic candidates must reside within the ward they seek to represent at the time of filing and must maintain that residency through the term. Citywide candidates must be Chicago residents. The Illinois Election Code sets no property ownership requirement for any municipal office.
For a broader orientation to how Chicago's electoral structure connects to its overall governance framework, the home page provides an overview of city institutions and their relationships. Questions about redistricting that alter ward boundaries — directly affecting which voters participate in a given aldermanic race — are addressed on the Chicago redistricting and reapportionment page.
References
- Chicago Board of Election Commissioners
- Illinois Election Code, 10 ILCS 5
- Illinois Municipal Code, 65 ILCS 5
- Illinois General Assembly — Full Text of 10 ILCS 5/10-9 (Electoral Board)
- Illinois General Assembly — Full Text of 10 ILCS 5/19A-15 (Early Voting)
- Illinois General Assembly — Full Text of 65 ILCS 5/3.1-10-50 (Vacancy Appointments)
- Illinois General Assembly — Full Text of 10 ILCS 5/17-16.1 (Write-In Declaration)
- Chicago Board of Election Commissioners — 2019 Primary Election Results