Bangalore urban district recorded 52.83 percent voting, the state election authorities said while the state average was 69 percent of the over 40 million voters.
In the last assembly poll in 2008, the turnout was around 45 percent.
In contrast Bangalore rural district recorded the highest turnout on Sunday with 77.95 percent voting, the district-wise voting percentage given by the authorities shows.
The three other districts that recorded less than 60 percent voting were Gulbarga 59.83, Yadgir 58.88 and Bidar 54.98. All three are in the northern part of the state.
The rest of Karnataka's 30 districts had between 60 percent and over 77 percent voting.