Vietcombank sold the greenback at VND25,400, down 0.08% from Wednesday.
The State Bank of Vietnam set its reference rate 0.04% lower at VND24,245.
Unofficial exchange points sold the greenback at VND25,730, up 0.04%.
Globally the U.S. dollar was soft on Thursday after the Federal Reserve opened the door for an interest rate cut in September, helping keep the yen pinned near its highest since March in the wake of a hawkish pivot from the Bank of Japan, Reuters reported.
The dollar index, which measures the U.S. currency against six peers, was little changed at 104.02, having dropped 0.38% on Wednesday. The index fell 1.7% in July, its weakest monthly performance this year.
The euro last fetched $1.0825 after rising 1% in July, while sterling was at $1.2852 ahead of the policy decision from the Bank of England, where the central bank could cut rates but markets and economists remain far from certain.