Vietcombank sold the greenback at VND26,380, up 0.01% over the weekend. The currency gained 0.43% to around VND27,328 on the black market.
The State Bank of Vietnam hiked its reference rate by 0.01% to VND25,124.
Globally, the dollar started the first full trading week of the New Year on the front foot, rising to a 3-1/2-week peak versus the euro and a two-week high against the yen, Reuters reported.
The U.S. dollar index, which measures the greenback's strength against a basket of six currencies, was up 0.1% at 98.55 on Monday, extending recent gains into a fifth consecutive day.
The dollar added 0.1% to $1.1704 per euro, and earlier strengthened as far as $1.170025 for the first time since Dec. 11. It climbed 0.2% to 157.08 yen after reaching 157.255 for the first time since Dec. 22.
The dollar advanced 0.1% to $1.3443 per British pound. The Aussie declined 0.2% to $0.6682.
Currency traders largely looked past the United States' weekend raid in Venezuela and the capture of President Nicolas Maduro, focusing instead on a slate of U.S. macroeconomic indicators due this week that could be crucial in steering Federal Reserve policy.
A recent run of resilient U.S. data has markets contemplating a potentially slower pace of interest rate cuts this year, said Kyle Rodda, senior financial markets analyst at Capital.com.