More than 55 million Turkish citizens are expected to vote on constitutional reforms which are designed to replace the existing parliamentary system of governance with a presidential one.
Turkish people continue to make their way to voting booths after polls opened on Sunday across Turkey for a referendum on constitutional amendments proposed by the governing Justice and Development Party (AK Party) and backed by the Nationalist Movement Party (MHP).
Turkey's main opposition Republican People's Party (CHP) had been campaigning against the proposed change or in favour of "No". If "Yes" wins the contest against "No", Turkey will adopt the presidential form of government, scrapping the existing parliamentary system.
Turkey's President Recep Tayyip Erdogan and Prime Minister Binali Yildirim cast their ballots at their respective polling stations before midday.
More than 55 million Turkish citizens are expected to vote in today's referendum. Citizens will go to over 167,000 polling stations nationwide.
TRT World's correspondents bring more from across the country.
Who can vote?
People aged 18 or above can vote. Over a million voters are those who recently turned 18 and are eligible to cast their ballot for the first time.
Inmates – except for criminals convicted of intentional crime – will also be able to vote at 463 polling stations located inside state prisons.
Prisoners, who are in jail pending trial, and who are convicted of minor crimes, will be able to vote.
The voting process
Sunday's ballot papers have two sides with two different colours. Voters will indicate their choice by voting either "Evet" (Yes) on the white side of the paper or "Hayir" (No) on the brown side.Evet" (Yes) on the white side of the paper or "Hayir" (No) on the brown side.
Voters will affix a seal on the side they have chosen.
They will then place the ballot inside a yellow envelope that has the symbol of the Turkish Republic's Supreme Election Board on it and cast their ballots.
Voting will take place between 7 am and 4 pm in Turkey's eastern provinces of Adiyaman, Agri, Artvin, Bingol, Bitlis, Diyarbakir, Elazig, Erzincan, Erzurum, Gaziantep, Giresun, Gumushane, Hakkari, Kars, Malatya, Kahramanmaras, Mardin, Mus, Ordu, Rize, Siirt, Sivas, Trabzon, Tunceli, Sanliurfa, Van, Bayburt, Batman, Sirnak, Ardahan, Igdir, and Kilis.
For the rest of the country, voting stations will open at 8 am and close at 5 pm.