The US Open's middle weekend coincides with Labor Day, the U.S. federal holiday observed on the first Monday in September.
The tournament traditionally begins in late August and runs for two weeks, placing its second weekend—and the Monday immediately after it—around Labor Day. That timing is part of the event's familiar calendar identity and helps make the holiday weekend one of the busiest stretches for spectators.
Labor Day is often confused with Memorial Day or Independence Day because all three are major U.S. holidays associated with summer. Memorial Day falls in May, Independence Day is July 4, and Thanksgiving arrives in November. Labor Day instead marks the first Monday of September and honors the American labor movement.
The US Open's middle weekend is not the tournament's championship weekend. Singles finals are held during the final weekend, while the Labor Day period generally features late-round matches such as the third round and fourth round.