Violent unrest has erupted in several cities including the capital, Paris, and trade unions have promised to intensify their strike movement, leaving Macron to face the most dangerous challenge to his authority since the "Yellow Vest" revolt several years ago.
A decision to force the pension legislation through the lower-house National Assembly without a vote last Thursday sparked protests over the weekend, calls for more strikes and outrage about a manoeuvre widely seen as undemocratic.
Bringing the government down was "the only way of stopping the social and political crisis in this country," Charles de Courson, the author of one of the two no-confidence votes and France's longest-serving MP, told France Inter radio on Monday.
"If we continue like this, no one will control anything. That's what all the trade union leaders are telling us... that they're seeing things becoming more radical," he said.
"It's not a failure, it's a total train wreck," Laurent Berger, head of the moderate CFDT trade union told newspaper Liberation.
Monday's no-confidence votes look unlikely to pass, but the result could be tight. A successful no-confidence vote would fell the government and kill the legislation, which is set to raise the retirement age by two years to 64.
Macron's allies are in a minority in the lower house National Assembly, meaning they could be defeated if the opposition unites in sufficient numbers for one of the ballots, which are set for debate from 1500 GMT.
Finance Minister Bruno Le Maire on Sunday called the votes "a moment of truth" for the government.
Most analysts expect the government to survive on Monday, thanks to backing from the right-wing opposition Republicans party that controls 61 seats.
But the margin could be tight after a senior Republican lawmaker, Aurelien Pradie, said he would vote against the government because "I think it's the only way out. We need to move on to something else."
If the government falls, Macron would have the option of naming another one or dissolving the National Assembly and calling fresh legislative elections.
A survey on Sunday showed the head of state's personal rating at its lowest level since the height of the "Yellow Vest" crisis in 2019, with only 28 percent of respondents having a positive view of him.
Republicans leader Eric Ciotti, who has backed the pension reform, has also called on his fellow MPs not to "add chaos to chaos" by voting against the government, but his authority in the party has been severely undermined by rebels.
This report was sourced from Reuters and Agence France-Presse.
