The Freedom Party of Austria (German: Freiheitliche Partei Österreichs, FPÖ) is a political party in Austria, variously described as far-right, extremist, right-wing populist, and eurosceptic. It has been led by Herbert Kickl since 2021. It is the largest of five parties in the National Council, with 57 of the 183 seats, and won 28.85% of votes cast in the 2024 election and it is represented in all nine state legislatures. On a European level, the FPÖ is a founding member of the Patriots.eu (originally the Movement for a Europe of Nations and Freedom) and its six MEPs sit with the Patriots for Europe (PfE) group following the dissolution of its predecessor, Identity and Democracy (ID).

The FPÖ was founded in 1956 as the successor to the short-lived Federation of Independents (VdU), representing pan-Germanists and national liberals opposed to socialism and Catholic clericalism, represented by the Social Democratic Party of Austria (SPÖ) and the Austrian People's Party (ÖVP), respectively. Its first leader, Anton Reinthaller, was a former Nazi functionary and SS officer, but the FPÖ did not advocate far-right policies and presented itself as a centrist party. The FPÖ was long the third largest in Austria and had modest support. Under the leadership of Norbert Steger in the early 1980s, it sought to style itself on Germany's Free Democratic Party (FDP). The FPÖ gave external support to SPÖ chancellor Bruno Kreisky (SPÖ) after the 1970 election and joined Fred Sinowatz's government, as the SPÖ's junior partner, after the 1983 election.

Jörg Haider became leader of the party in 1986, after which it began an ideological turn towards right-wing populism. This resulted in a strong surge in electoral support, but also led the SPÖ to break ties, and a splinter in the form of the Liberal Forum in 1993. In the 1999 election, the FPÖ won 26.9% of the vote, becoming the second-most popular party, ahead of the ÖVP by around 500 votes. The two parties eventually reached a coalition agreement in which the ÖVP retained the office of chancellor. The FPÖ soon lost most of its popularity, falling to 10% in the 2002 election, but remained in government as junior partner. Internal tensions led Haider and much of the party leadership to leave in 2005, forming the Alliance for the Future of Austria (BZÖ), which replaced the FPÖ as governing partner. Heinz-Christian Strache then became leader, and the party gradually regained its popularity, peaking at 26.0% in the 2017 election. The FPÖ once again became junior partner in government with the ÖVP. In May 2019, the Ibiza affair led to the collapse of the government and the resignation of Strache from both the offices of vice-chancellor and party leader. The resulting snap election saw the FPÖ fall to 16.2% and return to opposition. On 30 June 2024, ANO 2011, the Freedom Party of Austria, and Fidesz created a new alliance named Patriots for Europe.

The FPÖ is a descendant of the pan-German and national liberal camp (Lager) dating back to the Revolutions of 1848 in the Habsburg areas. During the interwar era, the national liberal camp (gathered in the Greater German People's Party) fought against the mutually hostile Christian Social and Marxist camps in their struggles to structure the new republic according to their respective ideologies. After a short civil war, the Fatherland Front established the Federal State of Austria, an Austrofascist dictatorship, in 1934. By 1938, with the Anschluss of Austria into Nazi Germany, the national liberal camp (which had always striven for an inclusion of Austria into a Greater Germany) had been swallowed whole by Austrian National Socialism, and all other parties were eventually absorbed into Nazi totalitarianism. Both Socialists and Christian Socials were persecuted under the Nazi regime, and the national liberal camp was scarred after the war due to guilt by association with National Socialism.

In 1949, the Federation of Independents (VdU) was founded as a national liberal alternative to the main Austrian parties—the Social Democratic Party (SPÖ) and the Austrian People's Party (ÖVP), successors to the interwar-era Marxist and Christian Social parties. The VdU was founded by two liberal Salzburg journalists—former prisoners of Nazi Germany—who wanted to stay clear of the mainstream socialist and Catholic camps and feared that hostility following the hastily devised postwar denazification policy (which did not distinguish between party members and actual war criminals) might stimulate a revival of Nazism. Aiming to become a political home to everyone not a member of the two main parties, the VdU incorporated an array of political movements—including free-market liberals, populists, former Nazis and German nationalists, all of whom had been unable to join either of the two main parties. The VdU won 12% of the vote in the 1949 general election, but saw its support begin to decline soon afterward. It evolved into the FPÖ by 1955/56 after merging with the minor Freedom Party in 1955; a new party was formed on 17 October 1955, and its founding congress was held on 7 April 1956.

The FPÖ started shortly after the Austrian government effectively ended Austrian denazification, which many experts describe as half-hearted. This paved the way for former Nazis to once again gain positions of power, and indeed the first FPÖ party leader was Anton Reinthaller, a former Nazi Minister of Agriculture and SS officer. He had been asked by ÖVP Chancellor Julius Raab to take over the movement rather than let it be led by a more socialist-leaning group. At the time of the party's founding, former Nazis formed a greater percentage of FPÖ members than the other contemporary parties. Because of the many former Nazis in the party, it was seen as a right wing extremist party, and was excluded from government at every level until the mid 1960s, except for the 1957 presidential election, when it ran a joint candidate with the ÖVP, who lost. However over time the former Nazis rebranded themselves as centrists pursuing pragmatic, non-ideological policies, and the FPÖ presented itself as a moderate party. The FPÖ served as a vehicle for them to integrate in the Second Republic; the party was a coalition partner with both the SPÖ and ÖVP in regional and local politics, although it was excluded at the national level.

Reinthaller was replaced as leader in 1958 by Friedrich Peter (also a former SS officer), who led the party through the 1960s and 1970s and moved it towards the political centre. In 1966, the ÖVP–SPÖ Grand Coalition, which had governed Austria since the war was broken, was ended when the ÖVP gained enough votes to govern alone. In 1967 the more extreme faction in the FPÖ broke away and established the National Democratic Party, seen by some observers as a final shedding of the party's Nazi legacy. After the 1970 election, the FPÖ became the kingmaker and supported an SPÖ minority government led by Chancellor Bruno Kreisky. Under the influence of Kreisky, a new generation of liberals brought the FPÖ into the Liberal International in 1978. During the years under Peter the party never won more than 8% of the national vote in general elections, and generally did not have much political significance.

Liberal Norbert Steger was chosen as new FPÖ party leader in 1980; in an effort to gain popularity, he helped the FPÖ become established as a moderate centrist liberal party. His vision was to transform the FPÖ into an Austrian version of the German Free Democratic Party (FDP), focusing on free-market and anti-statist policies. In the 1980s, the Austrian political system began to change; the dominance of the SPÖ and ÖVP started to erode, and the Austrian electorate began to swing to the right. SPÖ leader Bruno Kreisky had encouraged the FPÖ's move to the centre, in order to establish an SPÖ-FPÖ alliance against the ÖVP. The 1983 general election was a watershed; the SPÖ lost its absolute majority in Parliament, which resulted in the formation of an SPÖ-FPÖ "Small Coalition". Ironically, the 1983 election result was the worst for the FPÖ in its history (it received slightly less than 5% of the vote), and during the next few years the party saw 2–3% support—or even less—in opinion polls. As a consequence, the party was soon torn by internal strife.