The core fight is between incumbent Prime Minister Benjamin Netanyahu of the right-wing Likud Party, and former military chief Benny Gantz, head of the centrist Blue and White alliance. Pre-election polls suggested the two main contenders were neck-and-neck and that they would need to rely on smaller parties to form a governing coalition. If Mr Netanyahu is reinstated, it would make him the longest-serving Prime Minister in Israeli history.
What is expected to happen?
Israel typically runs on a coalition government – no party has ever won a majority in Israel’s 120-seat parliament, the Knesset.
If pre-election polls are correct, Mr Netanyahu and Mr Gantz will win about 30 seats in the Knesset each.
More than 40 parties are contesting Tuesday’s election, but only about a dozen are expected to overcome a 3.25 percent threshold, allowing them to enter parliament with four seats or more.
Follow our LIVE updates for all the latest news and results as they come in
Negotiations to form a coalition are expected to start soon after polls close at 10pm local time (8pm BST).
Under the Israeli constitution, the next Prime Minister isn’t necessarily the person whose party wins the most votes.
It is usually the person who manages to bring together enough parties to control at least 61 of the 120 seats.
In Israel’s fragmented party system the advantage remains with Mr Netanyahu, 69, who still looks most likely to be able to form a new coalition government.
In a widely criticised move to lock down extra right-wing seats, Mr Netanyahu brokered a deal in February making it easier for candidates from an extreme-right wing party that many view as racist to enter parliament.
And on election day his Likud party sparked alarm by sending 1,200 observers equipped with hidden body cameras to polling stations in Arab communities.
But Benny Gantz, 59, while a newcomer to politics, has garnered widespread support with his promise to unite a country that had “lost its way”.
Casting his vote in Rosh Ha’ayin near Tel Aviv, Mr Gantz said: “This is a day of hope, a day of unity. I look into everyone’s eyes and know that we can connect.”
Follow our LIVE updates for all the latest news and results as they come in
When will we know the results?
When polls close at 10pm (8pm BST), exit polls will begin filtering in, with the initial count coming in over the course of the night.
Final results can take a few days, as ballot boxes are checked and votes come in from Israelis overseas, but the results should be obvious long before.
Once the votes are tallied, President Reuven Rivlin will ask political parties that have won parliamentary seats who they support for Prime Minister.
He will then pick a party leader to try to form a coalition, giving the candidate 28 days to do so, with a two-week extension if needed.