Two surveys, issued last night by private television channels, both gave the Zionist Union a four-seat lead over Likud.
A poll by Channel 10 showed Likud winning 20 seats compared with 24 for the Zionist Union. Channel 2's results also showed Likud four seats behind, 22 to 26.
Friday was the final day that opinion polls could legally be published before the vote on March 17.
The results echoed polls published earlier Friday, which both predicted the Zionist Union would edge out Likud.
Centre-right Yesh Atid is forecast to win 12 seats.
Although consistently trailing in the polls, Netanyahu has come out fighting, and analysts say he is still better placed than Zionist Union leader Isaac Herzog to form a coalition government after the election.
Israel's electoral system means that the government is not formed by the largest party, but by whichever party leader can build a coalition commanding a parliamentary majority.
