Vietcombank sold its dollar at VND25,473, 0.04% higher than Wednesday and highest since July 25.
The State Bank of Vietnam hiked its rate by 0.04% to VND24,260.
The greenback went up 0.23% to VND25,620 on the black market.
It has risen 4.22% against the dong since the beginning of the year.
Globally the U.S. dollar traded close to a three-month high against major peers on Thursday, underpinned by expectations for a slower pace interest rate cuts by the Federal Reserve and growing bets of a possible second Donald Trump presidency, Reuters reported.
The dollar index, which measures the currency against six rivals including the euro and yen, stood at 104.38, not far from the overnight high of 104.57, a level last seen on July 30.