The line will open right after the Ministry of Transport officially transfers the project to the city at an event Saturday, said Hanoi's Deputy Chairman Duong Duc Tuan.
"In the first 15 days of operation, passengers can ride the metro for free," he said Wednesday.
Passengers will be offered a card to board the train, which they will have to return after their journey, said Vu Hong Truong, director of Hanoi Railway One Member Limited Company.
After the free-fare period, tickets are expected to sell for VND8,000 (35 cents) per trip and VND15,000 for a full start-to-end journey.
The Cat Linh – Ha Dong line, Vietnam’s first metro, runs 13 kilometers on elevated tracks through 12 stations from downtown Dong Da District to Ha Dong District in the southwest of the capital.
A full trip will take 23 minutes if stopping at all stations.
There are now 52 bus routes running along the line, linked to 14 nearby bus stations, equipped with parking space for private vehicles.
In the first six months of operation, there will be six trains operating daily, with each running 10 minutes apart. Later, the city would adjust the number following actual demand.
Authorities hope the line would contribute to easing traffic jams across inner-city areas.
Work on the line, built by China Railway Sixth Group, started in 2011 and was originally scheduled for completion in 2013, but loan disbursement issues with China only resolved in December 2017 and other issues stalled progress for years.
The original cost had been estimated at VND8.77 trillion (almost $553 million) before it ballooned to over VND18 trillion, including VND4.13 trillion of the counterpart Vietnamese capital.
The metro was awarded a safety certificate by French consultant, Apave-Certifier-Tricc consortium, in April.