They have taken the total number of accounts to 2.63 million as of September, according to the Vietnam Securities Depository.
The highest monthly figure was in April, nearly 36,900, when the market began to recover from its bottom in March when Vietnam recorded a surge in the number of Covid-19 cases.
The accounts opened this year include over 1,900 by foreign individuals and organizations.
Analysts said the declining bank interest rates are causing more people to switch to stocks.
Earlier this month banks lowered their 12-month deposit rates to 5.8 percent, the lowest in years, after the State Bank of Vietnam cut its policy rates for the fourth time this year to boost the economy. The deposit rates were around 7 percent at the beginning of this year.
Data from Hanoi brokerage BaoViet Securities shows that growth in deposits slowed down from over 10 percent in recent years to 7.85 percent in the first seven months this year.
"It is likely that some of the deposits have been transferred to other asset classes, including stocks," the brokerage said in a report.
The VN-Index closed at 929.86 points on Tuesday, 40 percent up from this year’s bottom on March 31.