As of 9.25 p.m. (1825GMT), unofficial results showed Yes with 51.34 percent -- 24,789,242 votes -- while No had 48.66 percent, or 23,499,390 votes.
Turnout across the country was 87 percent.
Sunday's referendum asked voters to choose Yes or No on an 18-article bill that would see the country switch from a parliamentary to a presidential system, among other changes.
Provinces which voted most heavily for either Yes or No:
Yes in Bayburt (81.67 percent), Rize (75.56), Gumushane (75.16), Erzurum (74.50), Kahramanmaras (73.95), Cankiri (73.46), Bingol (72.67), Konya (72.88), Elazig (71.82), and Sivas (71.30).
No in Tunceli (80.35 percent), Sirnak (71.50), Kirklareli (71.33), Edirne (70.35), Mugla (69.19), Izmir (68.78), Hakkari (67.62), Diyarbakir (67.58), Igdir (65.14), and Batman (63.50).
YES CAMPAIGN BACKED BY AK PARTY AND MHP
The constitutional amendments proposed by the governing Justice and Development Party (AK Party) were backed by the Nationalist Movement Party (MHP). Turkey's main opposition Republican People's Party (CHP) had been campaigning for a "no" vote, against the proposed changes.
ANATOLIAN VOTED YES
An overwhelming majority of Turkey's Anatolian region voted "Yes" in the historic constitutional referendum, according to unofficial results.
Turkey's three biggest cities Istanbul, Ankara and Izmir, as well as the predominantly Kurdish southeast voted "No", however, the "Yes" campaign performed better than expected in the southeast where the region widely voted for pro-PKK HDP in the 2015 general elections.
"Yes" voters have rallied behind President Recep Tayyip Erdoğan, who they describe as a leader capable of steering Turkey to success in a time of terrorism infused turbulence, security threats and the aftermath of the July 15th coup attempt.
FROM A PARLIAMENTARY TO A PRESIDENTIAL SYSTEM
The victory for the "Yes" campaign means Turkey's constitution will be amended to replace the parliamentary system, scrap the office of the prime minister and transform the presidency from a ceremonial position to an executive one.
Turkey headed to the polls on Sunday in a referendum on a 18-article bill that would see the country switch from a parliamentary to a presidential system.
WHAT WILL CHANGE AFTER VICTORY OF YES VOTES
Turkey voted on these key points of the constitutional amendments :
• Position of the prime minister will be abolished
• The number of MPs will be increased to 600
• High-ranking public executives will be directly appointed by the president
• The president can be sent to the high court with 400 votes
• State of emergency will be declared by the president and approved by the parliament
• The president will not be required to dissociate from his/her political party
• Judiciary, in addition to independence, will also be defined as impartial
• Parliamentary and presidential elections will be held simultaneously every five years
• The parliament will be able to request an investigation into the president's affairs by passing a majority vote
• The president will appoint ministers and vice president(s)
• The Board of Judges and Prosecutors will be comprised of the minister of justice, the undersecretary, seven members appointed by the parliament, and four members appointed by the president
• The age requirement to become an MP will be lowered to 18
• The legislative prerogative of the Parliament will be maintained
• The investigation decree for the president requires 360 votes
• Both the president and the parliament will be able to request a re-election
• The president must get parliamentary approval for the budget
• Military courts will be restricted to disciplinary issues among military officers
