The elections are non-partisan and use a two-round system where the top two finishers compete in a second-round run-off if no candidate receives more than 50% of the vote in the first round.

[1] Five aldermen ran unopposed: Brian Hopkins (2nd ward), Scott Waguespack (32nd), Gilbert Villegas (36th), Brendan Reilly (42nd), and Nicholas Sposato (38th).

There were a total of 12 new aldermen elected: Daniel La Spata (1st ward), Stephanie Coleman (16th), Jeanette Taylor (20th), Michael Rodriguez (22nd), Byron Sigcho-Lopez (25th), Felix Cardona (31st), Rossana Rodríguez (33rd), Samantha Nugent (39th), Andre Vasquez (40th), Jim Gardiner (45th), Matt Martin (47th), and Maria Hadden (49th).

Candidates for city council are required to submit 473 valid signatures from registered voters in their ward to appear on the ballot.

[32][43] One write-in candidate filed: Organizations Incumbent ninth-term alderman Patrick J. O'Connor unsuccessfully sought reelection, being defeated by Andre Vasquez in a runoff.

[2] One write-in candidate filed: Incumbent second-term alderman Michele Smith won reelection, defeating Derek Lindblom in a runoff.

One write-in candidate filed: One candidate was removed from the ballot due to insufficient nominating petition signatures:[2] Organizations: Organizations: Newspapers: Officeholders Individuals Newspapers: Incumbent fourth-term alderman Tom Tunney won reelection.

The following candidate filed nominating petitions but withdrew before ballot certification:[2] One write-in candidate filed: Organizations: Incumbent second-term alderman James Cappleman won reelection, defeating Marianne Lalonde in a runoff by a margin of only 25 votes (0.09% of the votes cast in the runoff).

[123] (Website)(Facebook)(Twitter) (Website)(Facebook)(Twitter) Two write-in candidates filed: Two candidates were removed from the ballot due to insufficient nominating petition signatures:[2] Hadden and Moore both identify as progressives, but their policy positions differ sharply on a number of issues, including policing, accepting donations from developers, use of tax-increment financing, and charter school expansion.

[165] Incumbent first-term alderman Carlos Ramirez-Rosa was reelected, defeating Amanda Yu Dieterich, his sole challenger.

[2] One write-in candidate filed: Incumbent first-term alderman Nicholas Sposato was reelected, running unopposed on the ballot.

One write-in candidate filed: Newspapers Organizations Incumbent second-term alderman John Arena unsuccessfully sought reelection.

Three write-in candidates filed: Organizations Newspapers Incumbent second-term alderman Jason Ervin won reelection.

[215] Krupa walked back comments from 2016, in which he had declared himself to be a, "day one Trump supporter" to a reporter from the Chicago Reader.

[215] Krupa received support from 2018 Republican candidate for Illinois governor, Jeanne Ives, who helped fundraise for his campaign.

However, Quinn's campaign submitted 2,800 sworn affidavits to the Board of Elections, supposedly from residents that had claimed they never signed Krupa's petitions.

One write-in candidate filed: Organizations Newspapers Incumbent first-term alderman Derrick Curtis won reelection, defeating Chuks Onyezia, his sole challenger.

Two write-in candidate filed: Newspapers Incumbent alderman Silvana Tabares, who had been appointed by Mayor Rahm Emanuel in 2018, won reelection to a first full term, defeating Paulino Villarreal, her sole challenger.

One write-in candidate filed: One candidate was removed from the ballot due to insufficient nominating petition signatures:[2] Organizations Newspapers Organizations: Incumbent third-term alderman Pat Dowell won reelection, defeating Alexandria Willis, her sole challenger on the ballot.

[236] Incumbent alderman Sophia King, who had been appointed by Mayor Rahm Emanuel in 2016, won election to a first full term, defeating Ebony Lucas, her sole challenger on the ballot.

One write-in candidate filed: Organizations Newspapers Incumbent fifth-term alderman Leslie Hairston won reelection, defeating William Calloway in a runoff.

[200] First-term incumbent Susie Sadlowski Garza won reelection, defeating Robert "Bobby" Loncar, her sole challenger.

One write-in candidate filed: Organizations Newspapers Incumbent third-term alderman Willie Cochran did not run for reelection.

Two write-in candidates filed: One candidate was removed from the ballot due to insufficient nominating petition signatures:[2] Organizations Newspapers Newspapers Officeholders Incumbent alderman Carrie Austin won reelection, defeating Preston Brown Jr., her sole challenger on the ballot.