Japan’s 30-year bond yield hits all-time high as decades of cheap money unravel

Japan’s 30-year government bond yield surged to 4.18%, nearing an all-time high for a country that spent the better part of three decades synonymous with rock-bottom interest rates. The move is part of a broader rout in Japanese government bonds that has pushed the 10-year yield to 3%, a level not seen since 1996. For context, Japan’s public debt exceeds 200% of GDP. When the country that owes more relative to its economy than any other developed nation suddenly has to pay dramatically more to borrow, the math gets uncomfortable fast. The great Japanese bond repricing The 30-year JGB yield had already set a record of 4.20% back in May 2026, and the latest spike puts it within striking distance of that peak again. Yields on 20-year and 40-year JGBs have also approached record territory, following a trend from sub-3% levels earlier in the cycle. Several forces are converging to drive this selloff. Rising oil prices and geopolitical tensions in the Middle East have stoked inflation concerns globally. Japan, which imports virtually all of its energy, is particularly exposed to commodity-driven price pressures. Then there’s the fiscal side. Prime Minister Sanae Takaichi’s government has...