Centrist and former economy minister Emmanuel Macron and far-right leader Marine Le Pen will resume campaigning for another 10 days.
The Labour Day marches on May 1 and a live television debate between Mr Macron, 39, and Ms Le Pen, 48, two days later on May 3 will give both sides a chance to rally support.
Campaigning and polling must stop on May 5, leaving a day's grace before the May 7 presidential election.
Polls open at 8am (2pm in Singapore) and close at 8pm.
The winner is likely to be known within hours, but the swearing-in ceremony usually does not take place until several days after the election.