Vietcombank sold the greenback 0.06% higher at VND26,536.
The State Bank of Vietnam hiked its reference rate by 0.04% to VND25,273.
The dollar went up 0.11% to VND26,580 on the black market.
Globally the U.S. dollar hovered below a one-week high on Thursday and Asian stock markets were mixed as investors braced for three days of potentially market-moving news from the Federal Reserve's annual symposium in Jackson Hole, Reuters reported.
The dollar traded little changed at 147.38 yen.
The euro and sterling were flat at $1.1645 and $1.3454, respectively.
Oil prices edged higher as larger-than-expected declines in crude oil and fuel inventories in the U.S. supported expectations for steady demand.