Hungarians could start voting at 6 a.m. local time on Sunday. Polls will close at 7 p.m.
Independent opinion polls indicate that the opposition, led by Péter Magyar's social-conservative party Tisza - which has promised to fight corruption and be a more reliable partner for the EU and NATO - is far ahead of Orbán's pro-Russian Fidesz.
Both camps have made accusations of foreign interference during the election campaign in the Central European country of 9.5 million people.
Preliminary election results are expected late this evening at the earliest.
Viktor Orbán (born 1963) has been the Prime Minister of Hungary since 2010 and leads the conservative Fidesz party, which at the EU level is part of the far-right PFE group, together with the French National Rally and the Belgian Vlaams Belang.
Péter Magyar (born 1981) has been a Member of the European Parliament since 2024 and is leader of the opposition Tisza party, which at EU level is part of the Christian-democratic EPP group, alongside, among others, Sweden's M and KD.
