A plan for a new flag for the county was announced back in December 2019, in celebration of the coming bicentennial anniversary of Cook County in 2031.
The finalists include:
• "Freedom," by Jaime Fregoso. The flag features white for transparency, blue for the waters of Lake Michigan and the county's rivers, green for nature and parks, and yellow for the sun and peace.
• "Harmony," by Alex Tomy. The flag represents peace and unity – with blue for "the dedicated Cook County police force, our clear blue skies, and Lake Michigan," green for the Cook County forest preserves, a white line for the 13 rivers in Cook County and snowy winters; and semicircles for the initials of Cook County founder Daniel Cook. A nine-pointed star in the middle represents the nine regions of the county forest preserves.
• "I Will Banner," by Andrew Duffy. The blue stripes represent the importance of water in Cook County in a Y formation to honor the merging of the branches of the Chicago River at Wolf Point. The green stripes represent the forest preserves and line the blue stripes to symbolize a riverbank. The white background represents innovation and commerce. The six six-pointed red stars represent different parts of Cook County.
• "Our Star," by Sofia Hogue and Ryan Bradley. The yellow stripe represents prairie land, the dark blue Lake Michigan, the light blue Cook County rivers, and the white star the city of Chicago.
• "Strides for Cook County," by Charlye Hunt and Ryan White. The blue represents Lake Michigan and the green the forest preservers. The half-compass shows the five suburban regions – north, northwest, west, southwest, and south – and the white triangle in its center represents the city of Chicago. The colors are also "a representation of power within a community and how a community should be," the designers wrote.
• "The New Century Flag," by Tim Mellman. The wheel on the left represents O'Hare and Midway international airports, the Cook County invention of the Ferris wheel, and the geographic layout of Cook County. The blue vertical stripes represent Lake Michigan, the Chicago River, the Des Plaines River, and the Little Calumet River.
The guidelines for the design context forbade any text, lettering, or numbering or reference to the current Cook County flag, seal, or map. It also suggested a maximum of four colors.
The current Cook County flag was introduced in 1961. It was designed by four county employees and the county treasurer and was introduced by then-Cook County Board President Dan Ryan.
In a 2020 video with County Board President Toni Preckwinkle, Matt DeLeon, secretary to the Cook County Board of Commissioners, characterized the flag that has now flown for the past 61 years as "not a particularly inspired design."
"They basically took the seal of the county and replicated it on the flag and put the words 'Cook County' on it, which is standard operating procedure for a lot of flags," DeLeon said in the video. "But I think one of the things that has developed over time is an appreciation for how a flag can do a lot to represent the history, the geography, the people of a jurisdiction or of a region – and also the mission of that particular government."