On December 18, in Vietnam, the black market US dollar buy rate was VND 26,900 and the sell rate was VND 26,950, a change of 0 and 0, respectively, for a mid-market rate of VND 26,925 (down 0.00 percent), according to Ty Gia USD.
Meanwhile, the State Bank of Vietnam’s central exchange rate was set at VND 25,151, while the Google Finance mid-market rate stood at VND 26,330.
The spread between the SBV’s central exchange rate and black-market mid-market rates was VND 1,774 or 7.05 percent.
How Low Can the Vietnamese Dong Go? Why It’s Sliding & What Might Happen Next
Vietnam exchange rates, 18 December 2025
| 18 Dec | 17 Dec | Change | % | |
| Black Market: Mid-market | 26,925 | 26,925 | 0 | 0.00% |
| SBV: Central Exchange Rate | 25,151 | 25,146 | 5 | 0.02% |
| Google Finance: Mid Market Rate | 26,330 | 26,332 | -2 | -0.01% |
| Black Market: Buy | 26,900 | 26,900 | 0 | 0.00% |
| Black Market: Sell | 26,950 | 26,950 | 0 | 0.00% |
| Spread: SBV / Black Market MM | 1,774 | 1,779 | -5 | -0.28% |
| Spread: SBV / Black Market MM | 7.05% | 7.07% | – | – |
Open market operations
The State Bank of Vietnam conducted repo operations worth US$0.00 million for 7 days, US$0.00 million for 14 days, US$0.00 million for 28 days, US$0.00 million for 91 days, with no 7-day T-bills issued.
Vietnam open market operations, 18 December 2025
| 18 Dec | 17 Dec | |
| Repos – 7 Days US$ | $0 | $0 |
| Repos – 14 Days US$ | $0 | $0 |
| Repos – 28 Days US$ | $189,898,000 | $0 |
| Repos – 91 Days US$ | $189,898,000 | $0 |
| Total | $379,796,000 | $0 |
Vietnam’s Black Market Dong Dilemma: Unpacked
Interbank interest rates
Vietnam’s interbank interest rates fell across most tenors.
The overnight rate decreased to 5.26 percent (down 1.82 points).
The 1-week rate fell to 5.84 percent, and the 2-week rate fell to 6.40 percent.
The 1-month rate increased to 7.42 percent, while the 3-month and 6-month rates fell to 7.35 and fell to 6.50 percent respectively.
The 9-month tenor rose to 6.75 percent.
Vietnam interbank interest rates, 18 December 2025
| 18 Dec | 17 Dec | Change | |
| Overnight | 5.26 | 7.08 | -1.82 |
| 1 Week | 5.84 | 7.10 | -1.26 |
| 2 Weeks | 6.40 | 7.47 | -1.07 |
| 1 Month | 7.42 | 7.40 | 0.02 |
| 3 Months | 7.35 | 7.49 | -0.14 |
| 6 Months | 6.50 | 6.70 | -0.20 |
| 9 Months | 6.75 | 6.52 | 0.23 |