Authorities said 78,928,647 registered voters were expected to vote at 72,195 polling stations nationwide.

The election council said 864 candidates were standing for seats in the 16th National Assembly across 182 electoral units. 

Of those, 217 candidates were nominated by central authorities and 647 by local bodies, with a ratio of 1.73 candidates for each seat.

The candidate list includes 45.37 percent women, 21.64 percent under the age of 40, 21.76 percent from ethnic minority groups, and 7.41 percent non-party members, while five candidates are self-nominated, according to the council.

Across the country, voters are also electing representatives to provincial and grassroots People's Councils. 

At the provincial level, 4,217 candidates are contesting 2,552 seats, while 120,873 candidates are running for 72,611 positions at the commune level.

Senior leaders were among early voters on Sunday morning. 

To Lam, General Secretary of the Communist Party of Vietnam, voted at a polling station in Ba Dinh Ward, Hanoi, while Prime Minister Pham Minh Chinh cast his ballot at a polling station in the capital city's Tay Ho Ward.

Voting was also held in remote and coastal areas, including Truong Sa Island, Khanh Hoa Province in the East Vietnam Sea and mountainous border communities in northern provinces.

In the southern province of Ca Mau Province, more than 1.8 million voters were expected to vote at over 1,600 polling stations, while local authorities said about 96,800 voters were eligible to cast ballots on Phu Quoc Island, An Giang Province.

Polling stations opened early across the country and voting was scheduled to continue throughout the day.