The new assembly is due to be transformed with a new generation of lawmakers - younger, more female and more ethnically diverse winning seats in the afterglow of Macron's success in last month's presidential election.
The scale of the change is forecasted to be so large that some observers have compared the overhaul to 1958, the start of the present presidential system, or even the post-war rebirth of French democracy in 1945.
It is also entirely unexpected: Macron was unknown three years ago and initially given little chance of emerging as president, but he and his 15 month old Republique en Marche (Republic On the Move, (REM) party have tapped into widespread desire for change.
And yet despite the zest for renewal the vote has failed to generate much excitement.
Official statistics showed turnout at midday down more than three points over the last election in 2012 at 17.75 percent, revealing a degree of election fatigue.
REM and its allies are forecast to win 400-470 seats in the 577-strong parliament, one of the biggest post-war majorities that would give the pro-EU Macron a free hand to implement his business-friendly programme.
Desperately seeking an opposition
Sunday's voting is the decisive second round of the election after a first round last weekend that was topped by REM and which was also marked by low turnout.
If confirmed, REM's crushing win will come at the expense of France's traditional parties, the rightwing Republicans and Socialists, but also the far-right National Front which faces major disappointment.
The Socialists are set to be the biggest victim of voters' desire to reject establishment figures associated with years of high unemployment, social unrest and lost national confidence.
Pollsters predict the party will lose well over 200 seats after its five years in power under former president Francois Hollande, leaving them with only around 20.
"People are tired of always seeing the same faces," said Natacha Dumay, a 59 year old teacher voting in the northeastern Paris suburb of Pantin where Socialist former justice minister Elisabeth Guigou was voted out a week ago.
"Even if we don't know the new faces it's not important. We're not voting for individuals but for a programme," she added.
The main concern for observers and critics is the likely absence of any political counterweight to Macron, leading some to forecast that opposition could be led through street protests or in the media.
"Desperately seeking an opposition," declared the front page of Saturday's Le Parisien newspaper.
REM won 32 percent of the total number of votes cast in the first round, but this represented only about 15 percent of registered voters.
'Go and vote!' Prime Minister Edouard Philippe urged on Thursday, calling it both 'a right and a responsibility'.
Around half of REM's candidates are virtual unknowns drawn from diverse fields of academia, business or local activism. They include a mathematician, a bullfighter and a former Rwandan orphan.
"You could take a goat and give it Macron's endorsement and it would have a a good chance of being elected," political analyst Christophe Barbier joked recently.
In some areas of Paris, the comment prompted a guerrilla campaign to replace photographs of REM candidates with a picture of a goat on their posters outside voting stations.
The other half of Macron's loyalists are a mix of centrists and moderate left- and right-wing politicians drawn from established parties including ally MoDem.
Le Pen in action
Key battles on Sunday include far-right leader Marine Le Pen's attempt to win her first seat in parliament in the northeastern former coal mining town of Henin-Beaumont.
Her victory would be a rare bright spot for Le Pen's nationalist and anti-EU party which was once hoping to emerge as the principal opposition to Macron in parliament.
The firebrand and influential leader of new far-left party France Unbowed, Jean-Luc Melenchon, is also seeking a seat representing the Mediterranean port of Marseille.
Macron's programme includes radical labour market reforms, measures to deepen European integration and an overhaul of the social security system.
He has vowed to take on French unions by creating a system of 'flexi-security' inspired by Scandinavian countries which combines a solid state-funded safety net with company-friendly legislation.
His confident start at home, where he has concentrated on trying to restore the lost prestige of the president, and his decisive action on the international stage has led to a host of positive headlines.
The European front cover of The Economist magazine this week asks whether Macron is 'Europe's saviour' and depicts him walking on water.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)