Religion in Austria

Religion in Austria is predominantly Christianity, adhered to by 68.2% of the country's population according to the 2021 national survey conducted by Statistics Austria. Among Christians, 80.9% were Catholics, 7.2% were Orthodox Christians (mostly belonging to the Eastern Orthodox Church), 5.6% were Protestants, while the remaining 6.2% were other Christians, belonging to other denominations of the religion or not affiliated to any denomination. In the same census, 8.3% of the Austrians declared that their religion was Islam, 1.2% declared to believe in other non-Christian religions (including Buddhism, Hindusim, Judaism and others), and 22.4% declared they did not belong to any religion, denomination or religious community.

According to church membership data, in 2023 50.6% of the population were Catholics and 2.7% adhered to Protestant churches.

Austria was historically a strongly Catholic country, having been the centre of the Habsburg monarchy (1273–1918) which championed Catholicism. Although in the 16th century many Austrians converted to Protestantism, Lutheranism in particular, as the Protestant Reformation (begun in 1517) was spreading across Europe, the Habsburgs enacted measures of Counter-Reformation as early as 1527 and harshly repressed Austrian Protestantism, albeit a minority of Austrians remained Protestant. A few decades after the fall of the Habsburg monarchy at the end of the World War I, and the transformation of Austria into a federal republic, at least since the 1970s there has been a decline of Christianity (with the exception of Orthodox churches) and a proliferation of other religions, a process which has been particularly pronounced in the capital state of Vienna.

Between the censuses of 1971 and 2021, Christianity declined from 93.8% to 68.2% of the Austrian population (Catholicism from 87.4% to 55.2%, and Protestantism from 6% to 3.8%, while Orthodox Christianity grew from 2.2% to 4.9% between 2001 and 2021). During the same timespan, Islam grew from being the religion of 0.2% to 8.3% of the Austrian population, and the proportion of people neither affiliating with nor belonging to any religion grew from 4.3% to 22.4%.