On December 29, in Vietnam, the black market US dollar buy rate was VND 26,750 and the sell rate was VND 26,820, a change of 0 and 1,000, respectively, for a mid-market rate of VND 26,785 (down 1.83 percent), according to Ty Gia USD.
Meanwhile, the State Bank of Vietnam’s central exchange rate was set at VND 25,125, while the Google Finance mid-market rate stood at VND 26,282.
The spread between the SBV’s central exchange rate and black-market mid-market rates was VND 1,660 or 6.61 percent.
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Vietnam exchange rates, 29 December 2025
| 29 Dec | 26 Dec | Change | % | |
| Black Market: Mid-market | 26,785 | 27,285 | -500 | -1.83% |
| SBV: Central Exchange Rate | 25,125 | 25,128 | -3 | -0.01% |
| Google Finance: Mid Market Rate | 26,282 | 26,290 | -8 | -0.03% |
| Black Market: Buy | 26,750 | 26,750 | 0 | 0.00% |
| Black Market: Sell | 26,820 | 27,820 | -1,000 | -3.59% |
| Spread: SBV / Black Market MM | 1,660 | 2,157 | -497 | -23.04% |
| Spread: SBV / Black Market MM | 6.61% | 8.58% | – | – |
Open market operations
The State Bank of Vietnam conducted repo operations worth US$0.00 million for 7 days, US$190.24 million for 14 days, US$0.00 million for 28 days, US$188.98 million for 91 days, with no 7-day T-bills issued.
Vietnam open market operations, 29 December 2025
| 29 Dec | 26 Dec | |
| Repos – 7 Days US$ | $0 | $0 |
| Repos – 14 Days US$ | $190,244,500 | $36,076,382 |
| Repos – 28 Days US$ | $0 | $38,037,200 |
| Repos – 91 Days US$ | $188,983,940 | $0 |
| Total | $379,228,440 | $74,113,582 |
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Interbank interest rates
Vietnam’s interbank interest rates fell across most tenors.
The overnight rate decreased to 5.47 percent (down 0.84 points).
The 1-week rate fell to 5.87 percent, and the 2-week rate rose to 8.72 percent.
The 1-month rate increased to 8.38 percent, while the 3-month and 6-month rates rose to 7.82 and fell to 6.93 percent respectively.
The 9-month tenor was unchanged at 6.75 percent.
Vietnam interbank interest rates, 29 December 2025
| 29 Dec | 26 Dec | Change | |
| Overnight | 5.47 | 6.31 | -0.84 |
| 1 Week | 5.87 | 6.89 | -1.02 |
| 2 Weeks | 8.72 | 8.63 | 0.09 |
| 1 Month | 8.38 | 7.55 | 0.83 |
| 3 Months | 7.82 | 7.68 | 0.14 |
| 6 Months | 6.93 | 6.93 | 0.00 |
| 9 Months | 6.75 | 6.75 | 0.00 |