Big changes are coming to one of America’s most popular marathon destinations. Starting in 2027, the CIM Expansion (Expansion of the California International Marathon) will significantly expand its capacity, doubling its field size and introducing a more inclusive course time limit.
Following an announcement by Visit Sacramento at its annual State of Tourism event, the race—famous for its fast, point-to-point course from Folsom to the State Capitol—is poised to evolve into one of the largest marathons in the country.
Doubling Capacity with a Second Wave
For years, CIM has been a perennial sell-out, with demand consistently outstripping the current 10,000-runner registration limit. To accommodate this surging interest, race organizers are planning to implement a second wave start beginning in 2027.
This structural shift is made possible by a new agreement with Union Pacific. By negotiating a longer window for freight trains to hold their schedules along the race route, organizers have secured the necessary logistics to keep the course open longer and manage a significantly larger influx of athletes.
Extending the Finish Line
Perhaps the most impactful news for many runners is the extension of the course cutoff time. Historically, the CIM has operated under a strict six-hour time limit, a constraint necessitated by the original train schedules.
Starting in 2027, the cutoff will be extended to at least six hours and 45 minutes. This 45-minute expansion is a major win for the marathon community, opening the door for runners who have previously been deterred by the strict cap.
“You certainly have the pros and the die-hards who are going to be at the front of the pack,” said Mike Testa, president and CEO of Visit Sacramento. “But then you have a lot of people who just want to say they’ve done a marathon, but they train really hard for that. To be pulled off the course because of a time limit, it has to be heart-wrenching.”
What This Means for You
While the December 2026 race will proceed with current parameters, the 2027 expansion aims to cement CIM’s status as a must-run bucket-list event. By doubling its capacity, race director Scott Abbott projects that CIM could soon rank among the top five marathons in the United States by field size.
For those targeting Boston qualifying times, the race’s reputation remains intact. With its net elevation drop of 366 feet, CIM remains one of the fastest courses in the country, maintaining its status as a premier location for athletes chasing personal bests and Olympic Trials qualifiers.
Stay tuned to Marathon Journal for ongoing updates as the organizing committee finalizes details for the 2027 expansion.
