A total of 62.65 per cent voter turnout was registered till 3 pm in the state, with the polling process scheduled to end at 5 pm, they said.
Voting had commenced at 7 am in all 16 seats, as people were seen standing in queues outside polling booths.
In five seats, which have Maoist-hit pockets, the process concluded two hours early, the officials said.
The seats that went to polls are Borio (ST), Barhait (ST), Litipara (ST), Maheshpur (ST), Sikaripara (ST), Rajmahal, Pakur, Nalla, Jamtara, Dumka (ST), Jama (ST), Jarmundi, Sarath, Poreyahat, Godda and Mahagama.
Altogether 40,05,287 electorate, including 19,55,336 women and 30 third-gender voters, were found eligible to cast their vote, Jharkhand Chief Electoral Officer Vinay Kumar Choubey said.
Of the 5,389 polling stations in the state, 396 in Naxal-affected areas have been marked "critical" and 208 as "sensitive".
The Election Commission has set up 8,987 ballot units, 6,738 control units and 7,006 VVPAT machines.
BJP candidate and Jharkhand Agriculture Minister Randhir Singh is seeking re-election from Sarath constituency, while another saffron party nominee and Women and Child Development Minister Louis Marandi is pitted against JMM working president Hemant Soren in Dumka.
Marandi had defeated Soren in 2014 assembly elections.
The JMM leader is also contesting the polls from Barhait seat. His sister-in-law Sita Soren is seeking reelection from Jama seat.
Among others, former deputy chief minister and sitting JMM MLA Stephen Marandi is seeking re-election from Maheshpur and JD(U)'s Jharkhand unit chief and ex-MP salkhan Murmu is contesting the polls from Sikaripara.
Out of 81 assembly seats in the states, elections concluded in 65 constituencies in the previous four phases between November 30 and December 16.