Red appears on more national flags than any other colour: of the 193 UN member states, around 148 fly a flag with at least some red in it. The reasons fall into a handful of traditions. Revolutionary movements reached for it as the colour of blood spilled for freedom. Communist states adopted it as a direct ideological symbol. Regional movements built shared palettes around it, from the Pan-African and Pan-Arab colours to the Pan-Slavic tricolour. In Europe much of it is far older, inherited from medieval coats of arms and crosses, and Britain carried it across the world in the Union Jack. And plenty of countries chose red simply because it is bold, visible at a distance and easy to reproduce.
Revolution and independence
Red as the blood shed to win independence or overthrow the old order, from the French tricolour to the flags of Latin America’s liberation wars.
France · UnitedStates · Mexico · Haiti · Cuba · Colombia · Venezuela · Ecuador · Peru · Bolivia · Chile · Paraguay · Costa Rica · Dominican Republic · Italy · Germany · Portugal · Turkey · Algeria · Indonesia · Timor-Leste
Communist and socialist heritage
Red as the colour of the workers’ movement, adopted directly by one-party socialist states or inherited from Soviet-era designs.
China · Vietnam · North Korea · Laos · Angola · Mozambique · Belarus
Pan-African colours
Green, gold and red taken from Ethiopia, the continent’s symbol of independence, or red, black and green from the Pan-African movement.
Ethiopia · Ghana · Senegal · Mali · Guinea · Guinea-Bissau · Cameroon · Benin · Togo · Burkina Faso · Republic of the Congo · São Tomé and Príncipe · Kenya · Uganda · Malawi · Zimbabwe · South Sudan
Pan-Arab colours
Red, white, black and green, drawn from the banner of the 1916 Arab Revolt.
Egypt · Sudan · Libya · Iraq · Syria · Jordan · Yemen · Kuwait · United Arab Emirates
Pan-Slavic colours
Red, white and blue, modelled on the Russian tricolour and adopted across much of the Slavic world.
Russia · Serbia · Croatia · Slovenia · Slovakia · Czechia
Crosses and coats of arms
Red that comes from medieval heraldry: royal and noble arms, crusader crosses and the Nordic cross family.
Spain · Belgium · Netherlands · Luxembourg · Austria · Hungary · Poland · Latvia · Switzerland · Liechtenstein · Monaco · Andorra · Malta · Albania · Montenegro · Georgia · Denmark · Norway · Iceland
The Union Jack legacy
Red carried by Britain’s flag and passed on to former dominions and territories that still fly it in the canton or kept its colours.
United Kingdom · Canada · Australia · New Zealand · Fiji · Tuvalu
Red for other reasons
Courage, sacrifice, the rising sun, local legend or simply a strong colour: these flags use red prominently without belonging to one of the traditions above.
Europe
Armenia · Azerbaijan · Bulgaria · Lithuania · Moldova · Romania
Asia and the Middle East
Japan · South Korea · Mongolia · Nepal · Bangladesh · Sri Lanka · Maldives · Myanmar · Thailand · Cambodia · Malaysia · Singapore · Brunei · Philippines · Kyrgyzstan · Tajikistan · Turkmenistan · Uzbekistan · Iran · Lebanon · Oman · Bahrain · Qatar
Africa
Morocco · Tunisia · Chad · Central African Republic · DR Congo · Burundi · Eritrea · Djibouti · Comoros · Seychelles · Madagascar · Mauritius · Zambia · Namibia · South Africa · Eswatini · Equatorial Guinea · Gambia · Liberia · Cabo Verde
The Americas
Panama · Belize · Trinidad and Tobago · Antigua and Barbuda · Dominica · Grenada · Saint Kitts and Nevis · Guyana · Suriname
Oceania
Papua New Guinea · Samoa · Tonga · Kiribati · Vanuatu
Not counted above: Palestine and Taiwan also fly flags with red but are not UN member states. Ireland (green, white and orange), Rwanda (blue, yellow and green since 2001) and India (saffron rather than red) are often assumed to belong on this list but have no red.