The anti-EU far-right group founded in the 1950s by a former SS officer, stands to become kingmaker in an ultra-conservative coalition after Sebastian Kurz’s People’s Party stormed to victory with around 31 per cent of the vote, according to the latest exit polls.
The FPO was vying with the centre-left Social Democrats (SPO) for second place, with both parties between 26 and 27 per cent.
And now Mr Kurz could look to form a coalition with Heinz-Christian Strache’s FPO, after a 12-year absence from government.
The FPO was last part of a government in Austria between 2000 and 2005.
Dutch, French, British and German general elections have already battered the Brussels elite with the European Union being forced to row back on some of its most outlandish ideas.
Now the Alpine republic, one of the first to erect a razor wire fence during the migrant crisis, will decide its future course on immigration, labour and social policy.
There was a temptation after the Dutch and French elections this year to declare an end to the far-right populist wave in Europe.
But last month’s German election, which saw the anti-immigration Alternative for Germany (AfD) party surge into the Bundestag, and now the Austrian election, say otherwise.
Despite a hard shift right by the conservative OVP under Mr Kurz, the FPO appeared close to the all-time high of 26.9 it won in 1999.
That result paved the way for it to enter government, a move which prompted a horrified EU to impose sanctions against Austria.
But Sunday’s result could show that the refugee crisis of 2015 has left deep scars among European voters.
Austria was used as a gateway for nearly 900,000 migrants making their way to Germany.
It also received more than 68,000 applications for asylum in 2015.