Vietcombank sold the dollar at VND24,180, up 0.12% from Sunday.
The State Bank of Vietnam raised its reference rate by 0.08% to VND23,960.
The dollar was sold at VND24,170 on the black market, up 0.46%.
It has increased against the dong by 1.90% since the beginning of the year.
The dollar eased from a 12-week peak on Monday as traders weighed the U.S. monetary path after the Fed Chair Jerome Powell left open the possibility of further interest rate increases, while the yen hovered close to its lowest in over nine months, Reuters reported.
In an eagerly awaited speech at the annual Jackson Hole Economic Policy Symposium, Federal Reserve Chair Powell promised to move with care at upcoming meetings as he noted both progress made on easing price pressures as well as risks from the surprising strength of the U.S. economy.
The dollar index, which measures the U.S. currency against six rivals, eased 0.115% to 104.05, but not far from the 12-week high of 104.44 it touched on Friday. The index is up over 2% in August and set to snap a two-month losing streak.