US 20 continues in an east-southeast direction through the town center of Bloomingdale and becomes six lanes at the Bloomingdale-Roselle border. It maintains six lanes through a very high traffic corridor to Interstate 290 and onwards to Illinois Route 53 before it returns to four lanes while serving downtown Addison, paralleling Interstate 290 to the north. Past Elmhurst, the road overlaps Interstate 290 for a mile.
