Peter Tabuns (Interim) Marit Stiles The 2023 Ontario New Democratic Party leadership election was held in Toronto, on February 4, 2023.

[3] The leadership election was called after ONDP leader Andrea Horwath announced her resignation on June 2, 2022, in her concession speech on the night of the 2022 Ontario general election, in which the Progressive Conservative Party of Ontario won a second consecutive majority government under Doug Ford.

Former education critic Marit Stiles was the sole candidate in the contest when nominations closed on December 5.

The vote was initially expected to be held on March 4, but the NDP provincial council moved the date up to February 4.

The ONDP constitution (Article 8, Section 1.4) stipulates that: In July 2022, the party announced that the leadership vote will conclude by the first week of March 2023.