A Day or A-Day may refer to: * 20 October 1944, the day the Leyte Island Operation began * ''A Day'' (film), a 2017 South Korean film * A-Day (University of Alabama), an annual college football exhibition game in the United States *A-day (6 April 2006), the commencement of pension tax simplification in the United Kingdom *"A Day", a 2017 episode of the American Netflix series '' Love''

See also