Vietcombank sold the dollar at VND24,550, down 0.04% from Thursday.
The State Bank of Vietnam kept its reference rate unchanged at VND24,084.
The dollar was stable at VND24,550 on the black market.
It has gained over the dong by 3.5% since the beginning of the year.
Globally, the dollar charged toward a 12-week winning streak on Friday, though it remained mostly rangebound as markets looked to U.S. nonfarm payrolls data later in the day for clues on whether the Federal Reserve's hawkish messaging on rates will need tweaking, according to Reuters.
The dollar index, which earlier in the week hit a roughly 11-month high of 107.34, last settled at 106.43, but remained on track for 12 straight weeks of gains. The last time it clocked such a milestone was in 2014.
Against the euro , the greenback was similarly headed for a record winning run of 12 successive weeks.
The single currency was last 0.07% lower at $1.0541.