Vietcombank sold the dollar at VND25,454, down 0.004% from Monday.
The State Bank of Vietnam maintained its reference rate at VND24,245.
The dollar dropped 0.04% to VND25,870 on the black market.
It has increased against the dong by 4.23% since the beginning of the year.
The dollar fell a touch on Thursday although moves were largely subdued ahead of a U.S. inflation report due later in the day, while sterling firmed on receding expectations for an August rate cut from the Bank of England (BoE), Reuters reported.
The British pound rose to a one-month high of $1.28545 in early Asia trade, extending a 0.48% gain from the previous session after comments from BoE policymakers caused markets to scale back bets for an easing cycle to begin next month.