The extra day puts the U.S. Open in line with the Australian Open, which switched its start from Monday to Sunday a year ago, and the French Open, which was the first tennis major to make the move when it added a 15th day in 2006.

The 2025 U.S. Open will look a little different this year as the major tournament will begin on a Sunday for the first time in the Open Era, which began in 1968. The final major tournament on the year will start on Sunday, August 24 instead of beginning on the Monday.

The US Open is expanding to 15 days this year, shifting to a Sunday start for the first time in the Open era that began in 1968.