Vietcombank sold the greenback at VND26,100, up 0.15% from Thursday. The currency surged by 0.6% to VND26,385 on the black market.
The State Bank of Vietnam's reference rate inched up by 0.02% to VND24,898.
Globally, the euro held steady on Friday at $1.1374, while the Japanese yen traded at 142.32 per dollar and the offshore yuan at 7.3002, with all three showing little change, Bloomberg reported.
The dollar index, which tracks the greenback against six major currencies, edged down 0.01% to 99.375 late on Thursday, according to Xinhua News Agency.