Vietcombank sold the dollar 0.04% lower at VND24,830.
The State Bank of Vietnam raised its reference rate by 0.07% to VND24,194.
The greenback gained 0.44% to VND25,270 on the black market.
It has risen 1.60% against the dong since the beginning of the year.
Globally the dollar was steady in early trading on Tuesday, with the yen inching away from one-month highs as investors brace for U.S. inflation data and reassess expectations of a large interest rate cut from the Federal Reserve starting next week, Reuters reported.
The dollar was up 0.1% at 143.30 yen, creeping away from the one-month low of 141.75 touched on Friday. Sterling last fetched $1.3061, having touched a near three-week low of $1.3058 earlier in the session.
The dollar index, which measures the U.S. currency against six rivals, was at 101.69 after rising 0.4% on Monday. The index fell 0.5% last week as traders' expectations for rate cuts shifted.