Flag Day is a day to fly a flag of a certain area or a day set aside to honor an event specifically involving a national flag.
Flag Day may also refer to:
National days
editOther uses
edit- Flag day (computing), a large change
- Flag Day (film), a 2021 film by Sean Penn
- Flag Day (Hong Kong), a day for charity fundraising - also practised in Singapore
- "Flag Day" (song), a song by The Housemartins