Nation Alliance candidate Kemal Kılıçdaroğlu led the presidential runoff in Türkiye's largest metropolis Istanbul with 51.6% of the vote, with 99.9% of the ballot boxes opened, following a tight race with People's Alliance candidate Recep Tayyip Erdoğan.
Erdoğan followed Kılıçdaroğlu with 48.4%.
Countrywide, Erdoğan received 52.12% of the votes with over 98% of the ballot boxes opened.
Erdoğan emerged victorious in the first round of elections with 49.52% of the vote against Kılıçdaroğlu's 44.88%.
More than 64.1 million people are registered to vote, including over 1.92 million who had already cast their ballots at overseas polling stations.
A total of 191,885 ballot boxes were set up for voters in the country.
Overseas voting was held until May 24. As for customs gates, voters could cast their ballots until domestic polling stations closed on Sunday at 5 p.m. local time (2 p.m. GMT).
Millions of voters went to the polls on May 14 to elect the country's president and members of the 600-seat Parliament.
The ruling Justice and Development Party (AK Party)-led People's Alliance won a majority in the parliamentary polls.
