The Chicago Marathon is an annual marathon held in Chicago, Illinois, United States. It is one of the six World Marathon Majors and is also the largest marathon in the United States. In 2023, the marathon had over 45,000 finishers. The 2025 Chicago Marathon will be held on October 12, 2025. Registration for the 2025 marathon will open in the spring of 2024.
The Chicago Marathon is a popular race for both elite and recreational runners. The race course is flat and fast, and the city of Chicago provides a supportive and enthusiastic atmosphere. The marathon is also a major fundraiser for charities, with over $200 million raised since its inception.