Vietcombank sold the dollar at VND25,463, up 0.02% from Monday.
The State Bank of Vietnam kept its reference rate stable at VND24,245.
The dollar went up 0.04% to VND25,740 on the black market.
It has increased against the dong by 4.27% since the beginning of the year.
Globally the dollar was firm on Tuesday while the yen struggled on the weaker side of the 156 level, though trade was mostly rangebound as investors generally stuck to their views of the expected timing and extent of Federal Reserve rate cuts this year, Reuters reported.
Against the yen, the dollar rose 0.07% to 156.37 in the early Asian session.
The yen has traded in a tight range over the past few sessions as fears of further intervention from Japanese authorities deterred traders from pushing the currency to new lows.
However, the still-stark interest rate differentials between the U.S. and Japan maintained the appeal of the yen as a funding currency.