Civic nationalism, otherwise known as democratic nationalism, is a form of nationalism that adheres to traditional liberal values of freedom, tolerance, equality, and individual rights, and is not based on ethnocentrism. Civic nationalists often defend the value of national identity by saying that individuals need it as a partial shared aspect of their identity (an upper identity) in order to lead meaningful, autonomous lives and that democratic polities need a national identity to function properly. Liberal nationalism is used in the same sense as 'civic nationalism', but liberal ethnonationalism also exists, and "state nationalism" is a branch of civic nationalism, but it can also be illiberal.

Civic nationhood is a political identity built around shared citizenship within the state. Thus, a "civic nation" defines itself not by culture but by political institutions and liberal principles, which its citizens pledge to uphold. Membership in the civic nation is open to every person by citizenship, regardless of culture or ethnicity. Those who share these values are considered members of the nation and, in theory, a civic nation or state does not aim to promote one culture over another. German philosopher Jürgen Habermas has argued that immigrants to a liberal-democratic state need not assimilate into the host culture but only accept the principles of the country's constitution (constitutional patriotism).

Civic nationalism is frequently contrasted with ethnic nationalism. According to Donald Ipperciel, civic nationalism historically was a determining factor in the development of modern constitutional and democratic forms of government, whereas ethnic nationalism has been more associated with authoritarian rule and even dictatorship. Indeed, the 20th-century revival of civic nationalism played a key role in the ideological war against racism. However, as Umut Özkırımlı states, "civic" nations can be as intolerant and cruel as the so-called "ethnic" nations, citing French Jacobin techniques of persecution that were utilized by 20th-century fascists. Some argue civic nationalism inevitably involves an underlying ethnic concept of national belonging because abstract values cannot be related to a specific place.

Civic nationalism lies within the traditions of rationalism and liberalism, but as a form of nationalism it is contrasted with ethnic nationalism. Ernest Renan is often thought to be an early civic nationalist. Philosopher Hans Kohn was one of the first to differentiate civic nationalism from ethnic nationalism in his 1944 publication The Idea of Nationalism: A Study in Its Origins and Background. Membership of the civic nation is considered voluntary, as in Renan's classical definition in "Qu'est-ce qu'une nation?" of the nation as a "daily referendum" characterized by the "will to live together". Some authors criticize that definition used by Renan, based on a "daily referendum", because of the ambiguity of the concept and its idealization. They argue that the arguments used by Renan at the conference "What is a Nation?" are not consistent with his thinking. Civic-national ideals influenced the development of representative democracy in countries such as the United States and France (see the United States Declaration of Independence of 1776, and the Declaration of the Rights of Man and of the Citizen of 1789).

The Corsican nationalist movement organized around the FLNC is giving a civic definition of the Corsican nation ("destiny community") in the continuity of Pasquale Paoli and the ideas of the Lumières.

The Scottish National Party and Plaid Cymru, which advocate independence of their respective nations from the United Kingdom, proclaim themselves to be civic nationalist parties, in which they advocate the independence and popular sovereignty of the people living in their nation's society, not individual ethnic groups.

The Republican Left of Catalonia supports a civic Catalan independentism and defends a Catalan Republic based on republicanism and civic values within a diverse society.

The Union of Cypriots define its ideology as Cypriot nationalism, a civic nationalism that focuses on the shared identity of Greek Cypriots and Turkish Cypriots. It highlights both communities' common culture, heritage and traditions as well as economic, political, and social rights. It also supports the reunification of Cyprus and the end of foreign interference by Greece, Turkey, and the United Kingdom.