I used to think “buyback” meant the US was printing money to pay off its debt. It doesn’t. Here’s how it actually works, step by step. Step 1: Bond price and yield are linked A Treasury bond pays a fixed amount per year. The price changes every day because investors trade bonds with each other. - Pay €800 for a bond that pays €50/year → yield 6.25% - Pay €1,000 → yield 5% - Pay €1,250 → yield 4% Same bond, same €50. The higher the price, the lower the yield. Price up = yield down, price down = yield up. Everything else builds on this. Step 2: The buyback itself The Treasury announces it wants to buy back a certain amount of its older bonds (recent operations were around $4B each). It works like a reverse auction: 1. Investors who own old bonds offer them at a price. 2. The Treasury accepts the cheapest offers. 3. The investor gets cash, and the government no longer owes anything on that bond. It’s voluntary, and the Treasury pays the market price of that day. Step 3: Where does the money come from? This is the part I got wrong. - The Treasury collects taxes, spends and borrows. It cannot create money. - The Fed is the only one that can create money (QE). So the Treasury pays with cash it already has, or by selling short-term T-bills at the same moment. A T-bill is a loan of up to 1 year: you pay €980 today and get €1,000 back later. Result: the Treasury swaps long-term debt for short-term debt. The total debt stays the same and no new money enters the system. Step 4: Why do it? With fewer long bonds around and an extra buyer, bond prices go up. From step 1 we know that means yields go down. Long yields determine what mortgages, business loans and the government’s own borrowing cost. Lower long yields mean cheaper financing for everyone. The Treasury is also always there as a buyer, which makes the market less nervous. Step 5: The catch - It’s small: a few billion per operation against roughly $40T of debt. - It doesn’t fix the cause. Yields are rising because of worries about debt and inflation, and a buyback doesn’t remove either. - Rollover risk: T-bills mature quickly, so the Treasury has to borrow again soon. If rates are higher by then, it pays more. It’s like swapping a 30-year loan for a 1-year loan and hoping rates drop in time.