Dozens of voters lined up outside a school in Abidjan's Plateau district before the official 7 am (local time) start.
Incumbent President Alassane Ouattara was widely expected to prevail over a divided opposition and perhaps secure enough votes to avoid a runoff.
Voting started one hour late at the school but local election official Kassoume Toure said all materials had been received.
In 2010, Ouattara defeated incumbent Laurent Gbagbo who refused to concede, sparking the worst fighting the country has experienced since independence.
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Kone said under Ouattara's leadership his salary had increased for the first time in 10 years, from 250,000 CFA (USD 420) per month to 312,000 CFA (USD 520) per month.
Ouattara has touted an economic rebound and security gains although opponents say he has failed to reconcile the country or reduce poverty.
More than 6 million people are registered.
Three members of an original roster of 10 candidates have withdrawn from the process citing doubts about the vote's fairness.