China’s biggest banks have figured out a neat trick: pay customers more to park their dollars, then use those dollars to buy US Treasuries. It’s asset-liability management dressed up as financial diplomacy, and it’s reshaping capital flows between the world’s two largest economies.
Foreign-exchange deposits in China surged to $1.18 trillion by the end of July, a 17.9% jump year-over-year. That wall of dollars, fed by record trade surpluses, needed somewhere to go. US government debt, with yields north of 4.7%, turned out to be a pretty compelling destination.
The deposit rate play
For years, China’s Big Five state-owned banks kept dollar deposit rates capped at 2.8%, a ceiling that had been in place since 2023. That changed in June when banks started offering rates above 3% for balances exceeding $50,000.
The math made sense for depositors. Yuan deposit rates at major state banks sit at just 0.95%. Parking your money in dollars at more than three times that rate doesn’t require a finance degree to appreciate.
For the banks, those deposits created a new problem: what to do with all those dollars. Domestic safe assets denominated in foreign currency are scarce in China. Banking sources have described the situation as something resembling a “famine” of safe domestic options, which naturally pushed banks toward the deepest, most liquid bond market on the planet.
Why Treasuries, why now
The 10-year US Treasury yield climbed more than 30 basis points to 4.76% since early June, driven by persistent inflation concerns and a more optimistic growth outlook in the US. For Chinese banks holding dollar deposits paying out just over 3%, buying Treasuries at nearly 4.8% creates a healthy spread.
The timing is notable because Chinese authorities had previously urged banks to limit Treasury purchases amid broader geopolitical and market tensions. But the current wave of buying has a different character than earlier episodes that drew regulatory scrutiny.
The key distinction: these purchases are funded by customer dollar deposits, not by converting yuan into dollars. When banks convert yuan to buy foreign assets, it puts downward pressure on the domestic currency and raises alarms at the People’s Bank of China. When they’re simply deploying dollars that customers voluntarily deposited, the political optics are entirely different.
This structure also means the buying doesn’t directly weaken the yuan. If anything, by giving dollar holders an incentive to keep their funds in the banking system rather than moving them offshore, it helps stabilize onshore dollar liquidity.
The bigger picture
The fact that China’s trade surplus keeps generating enormous dollar inflows makes this dynamic self-reinforcing. As long as Chinese exporters are earning more dollars than the economy can absorb domestically, those dollars need to be parked somewhere safe and liquid. Treasuries fit the bill better than almost anything else.
The spread between a 0.95% yuan deposit and a 4.76% Treasury is simply too wide for banks to ignore, regulatory sensitivities or not.