On Tuesday, September 15, the yield on 10-year Japanese government bonds reached 3.04%, according to Trading Economics, with a close of 3.041% (Investing.com). That is the highest since September 1996: for the first time in three decades Japan's 10-year debt yields more than 3%. A month ago the yield was around 2.9%, a year ago about 1.6%, and the record low set during the era of negative rates was minus 0.29%.
Fig. 1. Japan 10-year JGB yield, daily, August 17 - September 15, 2026. Source: Investing.com.
Fig. 2. Japan 10-year JGB yield: from negative to a 30-year high. Source: Trading Economics, Investing.com.
The causes compound each other:
Fig. 3. Japan government bond yield curve, September 15, 2026. Source: Trading Economics.
There is another side. Optimists note that Japan has finally escaped deflation, that savers and banks are earning a return again, and that higher rates reflect rising prices and wages rather than disease. That is a fair argument, and it explains why the BoJ is willing to keep going. But for thirty years the economy was built around free money, and rebuilding it for 3% will be painful.
Fig. 1. Japan 10-year JGB yield, daily, August 17 - September 15, 2026. Source: Investing.com.
What exactly has broken
This is not a market fluctuation but the end of the system that has propped up Japan's economy since the 1990s. For years the Bank of Japan pinned yields near zero, bought bonds and kept its policy rate negative. Now the rate is 1.00%, the highest since September 1995, and on Friday the central bank is expected to raise it to 1.25%, a level unseen since April 1995. BoJ board member Hajime Takata has described 2026 as a "regime change."Fig. 2. Japan 10-year JGB yield: from negative to a 30-year high. Source: Trading Economics, Investing.com.
The causes compound each other:
- a global bond repricing: US 10-year yields are at 5.00%, UK at 5.39% and German at 3.54%, and Japanese paper is rising with them;
- energy and inflation: Brent is above $108 and Japan depends almost entirely on imported oil; inflation is 1.9% and has accelerated from 1.6%;
- fiscal risk: government debt is 248.7% of GDP (2025, Japan's Ministry of Finance), and markets are wary of the Takaichi government's fiscal expansion (The Japan News);
- outside pressure: US Treasury Secretary Scott Bessent has openly urged the BoJ to tighten policy to support the yen.
Fig. 3. Japan government bond yield curve, September 15, 2026. Source: Trading Economics.
Why this is bad for Japan
Japan is the most indebted large economy in the world. Debt at 248.7% of GDP means every move higher in yields quickly turns into budget spending: the longer rates stay high, the more expensive it becomes to refinance that debt. The Bank of Japan is caught in a vice. To curb inflation and support the yen it must raise rates, yet higher rates worsen the fiscal picture. And the yen remains weak, near 155 per dollar, which itself fuels import prices.There is another side. Optimists note that Japan has finally escaped deflation, that savers and banks are earning a return again, and that higher rates reflect rising prices and wages rather than disease. That is a fair argument, and it explains why the BoJ is willing to keep going. But for thirty years the economy was built around free money, and rebuilding it for 3% will be painful.
⚠ IMPORTANT
Verdict: a 10-year JGB yield above 3% is not an episode but a regime change that breaks a model in place since the 1990s. For Japan it is first and foremost bad news: with debt at 248.7% of GDP, higher rates accelerate debt servicing, squeeze the budget and leave the Bank of Japan with almost no way out. If the rate is raised to 1.25% on Friday, the long end of the curve will push above 4%, and the question will no longer be about yields but about the durability of the whole structure.