Opposition parties have pushed for the vote to be held in secret, hoping to encourage ANC lawmakers to vote Zuma out.
Opposition parties have pushed for the vote to be held in secret, hoping to encourage ANC lawmakers to vote Zuma out of office after a series of corruption scandals.
But the president retains strong support from many lawmakers in the African National Congress, which led the fight against apartheid.
In the last two years, Zuma has easily survived three votes of no confidence and a separate parliament vote to remove him from office.
Parliamentary Speaker Baleka Mbete on Sunday issued a statement saying the date for the no-confidence vote had been changed from August 3 to August 8, due to a scheduled cabinet meeting.
Mbete, a Zuma ally, will decide whether the vote is secret after a case brought to the Constitutional Court by opposition parties, who have called for ANC lawmakers to "vote with their conscience".
The no-confidence vote was initially scheduled for April but delayed to allow the court to rule.
The ANC has vowed to defeat the motion.
Zuma is due to step down as ANC head in December and as national president ahead of the 2019 election.
On Friday, he opened a party conference admitting that the ANC was beset by corruption and divisions that could threaten a hold on power that has prevailed since the end of apartheid in 1994.