The Chicago Cubs and Chicago White Sox both clinched postseason berths Thursday, creating a rare October scenario for the city and making 2026 just the fourth season in Major League Baseball history in which both Chicago clubs have reached the playoffs.

The Cubs punched their ticket with a 2-1 victory over the Miami Marlins at Wrigley Field, securing one of the National League's three Wild Card spots. The win gave Chicago its second consecutive postseason appearance after the Cubs also reached the playoffs in 2025.

The White Sox followed shortly afterward with a 9-1 victory over the Kansas City Royals. The win guaranteed Chicago no worse than one of the American League's three Wild Card positions, although the White Sox remained in contention for the AL Central title with the Cleveland Guardians.

The day also produced a milestone for Cubs outfielder Pete Crow-Armstrong, who joined the 40-40 club by stealing his 40th base to go with 45 home runs. He became just the seventh player in MLB history to reach 40 home runs and 40 stolen bases in the same season.

For the White Sox, the postseason berth represents an especially dramatic turnaround. Chicago had suffered consecutive 100-loss seasons before returning to October baseball, becoming the first MLB team to reach the playoffs immediately after back-to-back 100-loss campaigns.

The last time both Chicago teams reached the playoffs was 2020, when the COVID-shortened season expanded the postseason field. Neither club advanced beyond the Wild Card round that year. The Cubs lost to the Miami Marlins, while the White Sox fell to the Oakland Athletics.

Before 2020, the Cubs and White Sox had reached the postseason together in 2008. Both teams were eliminated in the Division Series, with the Los Angeles Dodgers sweeping the Cubs and the Tampa Bay Rays defeating the White Sox in four games.

The first time both clubs reached the postseason together came in 1906, when the two Chicago teams met in the World Series. The White Sox defeated the Cubs four games to two, making that the only season in which Chicago's two MLB teams have faced each other for a championship.

The 2026 postseason will therefore mark only the fourth time that both sides of Chicago have played October baseball in the same season, and Thursday marked the first time the Cubs and White Sox have ever clinched their postseason spots on the same day.