The elections, postponed for two months in Anbar and Nineveh provinces due to security concerns, come amid a long-running political deadlock and are seen as a key gauge of politicians' popularity ahead of general elections next year.
Some 2.8 million voters in Anbar and Nineveh, which lie in Iraq's west and north respectively, will choose between 1,185 candidates from 44 political parties jostling for 69 provincial council seats in all.
The polls will be taking place two months after elections were held in 12 other Iraqi provinces in the centre and south of the country.
Tight security measures were put in place for the elections in the two provinces where nine candidates have been killed in the run-up to the vote, according to the United Nations.
Nineveh, for example, implemented a province-wide ban on vehicle traffic.
On the eve of the elections, a suicide bomber killed a local party chief in the province and four of his relatives.
The provincial elections are seen as a key gauge of the popularity of Prime Minister Nuri al-Maliki, who has been charged by his critics of consolidating power, ahead of parliamentary elections next year.
No landmark legislation has been passed since 2010 general elections, and analysts say a prolonged political stalemate and months-long protests in Sunni areas have contributed to a surge in nationwide violence which has sparked fears of a return to the brutal sectarian war that blighted Iraq in 2006 and 2007.
Provincial councils are responsible for nominating governors who take charge of the provinces' administration, finances and reconstruction projects, and have sway over key local issues such as sewerage and other services.
