Vietcombank sold the greenback 0.01% higher at VND26,412.
On the black market the dollar dropped 0.37% to VND27,150.
Globally the U.S. dollar rose against major currencies in choppy trading ahead of a week packed with central bank meetings and headlined by the Federal Reserve, where an interest rate cut is all but priced in, but investors braced for signals of a milder easing cycle than expected, Reuters reported.
The dollar index was last up 0.1% at 99.07. Against the Swiss franc, the greenback rose 0.2% to 0.8066 franc.
In other currencies, the Australian dollar briefly touched a high of US$0.6649, the highest since mid-September, to last trade down 0.3% at US$0.6621.