Vietcombank sold the greenback 0.08% higher at VND25,740.
The State Bank of Vietnam raised its reference rate by 0.11% to VND24,696.
Unofficial exchange points sold the dollar 0.16% higher at VND25,770.
The dollar has risen 0.74% against the dong since the beginning of the year.
Globally the U.S. dollar firmed above an 11-week trough on Thursday as vague pledges from President Donald Trump to impose tariffs on Europe and further delays to levies planned for Canada and Mexico stoked uncertainty, Reuters reported.
The euro was down 0.06% at $1.0479, with traders also awaiting any progress on efforts to form a government in Germany following the election victory of the country's.
The dollar index, which measures the U.S. currency against the euro and a handful of other major peers, rose 0.10% to 106.56, edging further off a more than two-month low of 106.12 touched on Monday.