Surveys have shut in the Turkish races - where voters are choosing whether to concede President Recep Tayyip Erdogan a second five-year term.
He has confronted an intense fight with Muharrem Ince, an inside left hopeful who has stimulated the restriction.
Making his own choice, the president guaranteed there had been a high turnout. To start with comes about are expected later on Sunday.
In the event that Mr Erdogan wins, he will embrace major new powers that commentators say will debilitate vote based run the show.
He is wanting to get over half of the vote in this poll to abstain from setting off to a second round.
And additionally the administration, voters are likewise picking individuals from parliament.
Turkey stays under a highly sensitive situation forced in the outcome of a fizzled upset in July 2016.
These decisions were initially planned for November 2019 yet were presented by Mr Erdogan.
"Turkey is experiencing a vote based transformation with this race," the president told correspondents after he voted in Istanbul.
In the mean time Turkey's appointive bonus said it would investigate reports of tally stuffing and terrorizing of eyewitnesses in the southern Urfa area, which fringes Syria.
What do the hopefuls say in regards to each other?
Mr Erdogan and Mr Ince both held immense encourages on Saturday, their last day of crusading - and each marked the other unfit to run Turkey
Mr Ince, whose blazing battling has rejuvenated Turkey's discouraged resistance, guaranteed to push back what he portrayed as a slide into tyrant manage under Mr Erdogan.
"On the off chance that Erdogan wins, your telephones will keep on being tuned in to... Dread will keep on reigning," he told no less than a million people assembled in Istanbul. "On the off chance that Ince wins, the courts will be autonomous."
Mr Ince likewise said that if chose, he would lift Turkey's highly sensitive situation inside 48 hours. Crisis control enables the legislature to sidestep parliament.
At his own particular rally, President Erdogan - who was leader for a long time before getting to be president in 2014 - utilized a vicious illustration to condense his sought after outcome, asking supporters, "Would we say we will give them an Ottoman slap [a procedure for thumping somebody out] tomorrow?"
He denounced Mr Ince - a previous instructor and MP of 16 years - of without the aptitudes to lead.
"It's one thing to be a material science instructor, it's something else to run a nation," Mr Erdogan said. "Being president needs encounter."