Polls opened at 7 a.m. (5:00 GMT) in Rome, Milan, Naples, Turin, Bologna, Rimini, and the southern province of Calabria. More than 12 million Italians are eligible to cast ballots.
All eyes are on the polls in the capital and other major cities. A mayoral candidate needs to secure 50% of the vote plus one to avoid a runoff. The second round will be held from 17-18 October.
Polling stations will close at 3 p.m. on 4 October. Coronavirus restrictions are being enforced, including mandatory mask wearing and social distancing. People who do not have a digital COVID-19 pass are still allowed to vote.