Andry Rajoelina and Marc Ravalomanana both failed to secure 50 percent of the vote required for a first-round win and the run-off scheduled for December 19.
Two former presidents of Madagascar, Andry Rajoelina and Marc Ravalomanana, came out top in the country's election, results showed Saturday, and are set to compete in a run-off.
Neither won the 50 percent required for a first-round win, with Rajoelina on 39.19 percent and Ravalomanana on 35.29 percent, according to final results from the CENI election commission, with the run-off scheduled for December 19.
Hery Rajaonarimampianina, who was running to hold onto power, secured only 8.84 percent of the vote, the commission said, adding turnout at last week's election was 54.3 percent.
All three leading candidates, out of 36 runners, have raised allegations of fraud and malpractice by election authorities, and the result could be subject to a fierce legal battle.
"We have adopted three rules of conduct: transparency, impartiality and independence," CENI president Hery Rakotomanana said as the final results were announced.
"We have not accepted any orders from anyone in this election... no favours have been given to anyone."
Madagascar is one of the world's poorest countries, according to World Bank data, with almost four in five people living in grinding poverty on the Indian Ocean island.
But the frontrunners spent huge sums on flashy campaign rallies, helicopters and giveaways such as free T-shirts for supporters.
Past political violence
A European Union observer mission said in a report on Monday that it had "noted candidates committed breaches" ahead of the November 7 poll, but concluded that the election was well organised overall.
Both Ravalomanana and Rajoelina were banned from contesting the last election in 2013 under international pressure to avoid a repeat of political violence that engulfed the island in 2009.
Ravalomanana, 68, and Rajoelina, 44, are bitter rivals. It is the first time they have faced each other at the ballot box.
Ravalomanana ruled from 2002 to 2009 until he was ousted in a military-backed coup that installed Rajoelina who was in power until 2014.
Rajaonarimampianina succeeded him, ruling until earlier this year.
Rajaonarimampianina's attempts to change the electoral laws this year backfired, sparking nearly three months of sometimes violent protests in the capital Antananarivo.
The demonstrators forced Rajaonarimampianina to accept a "consensus" government tasked with organising the election in the former French colony, which is burdened by a long history of coups and unrest.
African Union (AU) observers have called on the contenders to "show restraint and respect the law".