Vietcombank sold the dollar at VND24,420, up 0.12% from Thursday.
The State Bank of Vietnam raised its reference rate by 0.05% to VND23,927.
The dollar was unchanged at VND24,560 on the black market.
It has increased by 2.91% since the beginning of the year.
Globally, the dollar was restrained on Friday by uncertainty over the path of U.S. interest rates, while the euro held overnight gains as data hinted that the downturn in the euro zone may be easing, Reuters reported.
With U.S. markets closed on Thursday and due for a shorter trading session on Friday for Thanksgiving, currencies are likely to trade narrowly but with some volatility as liquidity is expected to remain thin.
The dollar index, which measures the U.S. currency with six peers, eased 0.029% to 103.73, staying close to the two-and-a-half month low of 103.17 it touched earlier this week.
The index is down 2.8% for the month, on course for its weakest monthly performance in a year on rising expectations that the Federal Reserve is done raising interest rates and could start cutting rates next year.