The Action democratique du Quebec won't be getting a new permanent leader until next February.
Those interested in replacing Mario Dumont have until Sept. 22 to declare their candidacy.
They must get 1,000 signatures, including at least 60 in 12 different regions of the province, and pay a deposit of $15,000.
All party members will be eligible to vote, with the winner being announced next Feb. 7.
Sylvie Roy, an ADQ member of the legislature, will continue serving as interim leader.
Dumont stepped down earlier this month after the party won only seven out of 125 seats in last December's election.