|A Saudi man casts his vote at a polling center in Jeddah|
Voters were lined up at polling centers in the commercial capital, Jeddah, Taef and Islam's holiest cities, Mecca and Medina.
Officials say initial results could be expected Friday.
The first two rounds of voting were held in February and March in the capital, Riyadh and eastern and southern regions of the country.
Minority Shi'ite candidates have won a majority of seats in municipal councils in the smaller towns of the oil-rich Eastern Province, but Sunni candidates dominated the field in the principal cities.
The elections, which exclude women, are part of a cautious program of political reform in Saudi Arabia, which has faced international pressure to democratize its system
Some information for this report provided by AFP and Reuters.