Red flag

Red flag may refer to:

Signs and warnings

Red flag (idiom), a literal or metaphorical warning
Red flag (American slavery), signal of an upcoming slave sale
Red flag warning, issued by the National Weather Service in the United States
Bloody flag, maritime flag signaling an intention to give battle with no quarter (fight to the death)
Red flag in motor racing, when conditions are too dangerous to continue the session
Red flag in gridiron football
Red flag used by a railway conductor

Red flag, a common name for Iris fulva, a flowering plant endemic to the southern and central United States

Red flag law, a state law in the US that allows temporary confiscation of firearms
Red flag traffic laws, in the UK and US in the 19th century affecting drivers of early automobiles
- "Red Flag Act", a Locomotive Act, the 19th-century British road law
Red Flags Rule, to help prevent identity theft in the US

Red Flag (magazine), published by the Chinese Communist Party
Red Flag (newspaper), by the Trotskyist organisation Socialist Alternative in Australia
Shimbun Akahata ('Newspaper Red Flag'), of the Japanese Communist Party
Bandera Roja (La Paz), a socialist newspaper in Bolivia of the 1920s
Die Rote Fahne ('The Red Flag'), a German communist newspaper created on 9 November 1918 by Karl Liebknecht and Rosa Luxemburg

"The Red Flag", a socialist song
"Bandiera Rossa" ('Red Flag'), a famous song of the Italian labour movement
"The Standard of Revolt" (French: Le drapeau rouge 'the red flag'), a French socialist song
"Red Flag" (song), by Billy Talent, 2006
"Red Flags" (song), by Mimi Webb, 2023
"Red Flags", a 2023 song by Josh Ross
"Red Flags", a 2023 song by Plain White T's
"Red Flag", a song by Slipknot from the 2019 album We Are Not Your Kind
"Red Flag", a song by Gwen Stefani from the 2016 album This Is What the Truth Feels Like
"Red Flag", a song by Kesha from the 2025 album Period
"Red Flag Day", a song by U2 from the 2017 album Songs of Experience
"Red Flags", a song by Chris Brown from the 2023 album 11:11
"Red Flags", a song by Tinashe from the 2024 album Quantum Baby

Red Flag AB, a company based in Stockholm and Malta
Red Flag Group, a compliance risk firm in Hong Kong
Red Flag Linux, software
Red Flag Publishing House, a book publisher based in China
Exercise Red Flag, a series of United States Air Force training exercises
- Red Flag – Alaska
Red Flag, several classes of locomotives by Kim Chong-t'ae Electric Locomotive Works, in North Korea
Charles E. Taylor (politician), known as "Red Flag" Taylor, an American politician