Vietcombank sold the dollar at VND24,750, up 0.12% from Monday.
The State Bank of Vietnam hiked its reference rate by 0.02% to VND24,141.
The dollar fell 0.12% to VND25,000 on the black market. It has risen 1.26% against the dong since the beginning of the year.
Globally the dollar traded near its lowest levels of the year on Tuesday, on the eve of the expected the start to a U.S. easing cycle that markets are betting may begin with an outsized rate cut, Reuters reported.
The yen made a jaunt to the stronger side of 140 during holiday thinned trade on Monday, and had eased back to 140.96 as dealers returned to their desks in Tokyo.
The euro rallied overnight to $1.1138 and traded around there early in the Asia session, not far from the year's high against the dollar of $1.1201.
The dollar index weakened 0.4% overnight to 100.7, not far from its 2024 low made last month at 100.51.