Unofficial exchange points sold the greenback 0.23% higher at VND25,900.
Vietcombank kept its rate stable at VND25,468.
The State Bank of Vietnam’s reference rate was unchanged at VND24,245.
The dollar has gone up by 4.29% since the beginning of the year.
Globally the dollar edged higher against other major currencies on Friday, hitting a fresh eight-week high against the yen as data showed a strong U.S. economy and as the Federal Reserve's patient approach to interest-rate cuts stood in contrast to more dovish peers, Reuters reported.
The dollar index, which measures the currency against six others, was up 0.2% at 105.81 in New York afternoon trading.
It had spiked 0.41% overnight, erasing declines for the week, following a second successive rate cut at the Swiss National Bank and hints from the Bank of England of a reduction in August.