Vietcombank sold the greenback 0.02% higher at VND26,355.
The dollar gained 0.14% to VND27,840 on the black market.
Globally the dollar held just below multi-month highs on Thursday, with a recovery in appetite for riskier assets pulling it off recent peaks, while sterling was under pressure ahead of a Bank of England meeting where investors anticipate a dovish tone, Reuters reported.
At $1.1495 against the euro the dollar has not budged a great deal, though it sits a fraction weaker from Tuesday's three-month top of $1.1469.
"The market was a little bit more sensitive to the improvement in risk appetite," said National Australia Bank senior currency strategist Rodrigo Catril in Sydney.
Bigger moves, however, and especially any durable fall in the dollar would need a clearer picture of the U.S. economy than is currently available, he said, with investors and policymakers flying blind as a prolonged government shutdown halts data publication.
"The dollar carries better than the yen or the euro," he said, referring to higher U.S. government bond yields. "So for now, gravity tells you the dollar will be supported."