The drive-in is planned at 1016 W. Wilson Ave., in a vacant lot west of a McDonald's location.
Abby Sullivan, one of the alderman's aides, said this week that Sonic is working on getting a building permit after obtaining a special-use permit for a drive-thru restaurant from the Zoning Board of Appeals in March.
Sonic is "hoping to be open by the end of the summer," and anticipates breaking ground soon, Sullivan said.
The Oklahoma-based chain has about 3,500 restaurants countrywide. Sonic is known for carhop service and offerings such as quarter-pound Coney dogs, Tater Tots and Cherry Limeades.
The average store does about $1 million in annual sales, the company said.