US Holidays Calendar - Sep 2026 en Copyright 2026, holiday0021@icaldates.com Mon Sep 7 2026 /day.php?getdate=20260907&cal=US%2BHolidays Mon Sep 7 2026 All day event: 1st Monday of September holiday0017@icaldates.com Sun Sep 13 2026 /day.php?getdate=20260913&cal=US%2BHolidays Sun Sep 13 2026 All day event: First Sunday after Labor Day