Germany's 30-Year Yield Hits a 15-Year High: The End of Bund Scarcity

Berlin can now borrow for a generation at its highest cost since 2011. The market is pricing the end of German fiscal exceptionalism — with consequences for bond funds, European stocks and the euro.

Germany's 30-year government bond now yields about 3.7%, the most since 2011; its 10-year bond sits just above 3.2%, also a fifteen-year high. Both records fell in the third week of August, as the 30-year American Treasury blew through 5.3%, its highest since 2007, and long-dated yields in Japan, France and Britain climbed alongside. When the world's safest governments simultaneously pay more to borrow for a generation, the machinery of the bond market has shifted, not merely its mood. For an American investor the German figure is no foreign curiosity: it is the benchmark for Europe's biggest economy, a setting level for international bond funds and European equities, and a leading indicator for long rates at home.

The obvious trigger is a war. A conflict nearly six months old between America and Iran has effectively closed the Strait of Hormuz, keeping oil above $90 a barrel and stoking the inflation that eats away at a 30-year promise. With German inflation at 2.8% and rising, lenders demand more. But the war explains the timing, not the direction of travel.

For the fifteen years before 2025, Germany paid the world to take the opposite view. Its constitutional "debt brake", enacted in 2009, and a government temperament that ran budget surpluses meant the federal state barely borrowed at all. Its bonds became Europe's one indisputably risk-free asset — benchmark, collateral and hedge rolled into one. For years the 10-year Bund yielded less than nothing; investors handed Berlin money because the alternative, lending to almost anyone else in Europe, was worse. German frugality was the promise that the currency union would not be run by its most indebted members.

That era ended in March 2025, when the Bundestag voted 513 to 207 to loosen the debt brake, exempting defence spending above 1% of GDP from the borrowing limit and creating a €500bn off-budget fund for infrastructure and climate. The change was sold as the price of a rearming, unreliable America. Economically it was Germany's consent to become a normal borrower — and a large one. The market noticed before the war did: the 30-year yield jumped about 40 basis points in the first half of 2025, largely on the creation of the fund.

The arithmetic has followed. Berlin plans to sell a record €512bn of federal securities this year, a fifth more than in 2025, to rearm the Bundeswehr and rebuild roads and railways, and its 2026 budget involves new borrowing of roughly €180bn — second only to the covid year. The supply keeps coming: Commerzbank, a bank, expects German issuance to rise to €400bn in 2027, and Barclays, another, projects a record €1.54tn of eurozone bonds next year. Much of the debt buys something the eurozone has chosen: defence spending of 2.83% of GDP this year, heading toward 3.56% by 2029.

The old absorber has left the room. The European Central Bank, which bought almost everything in sight for a decade, is buying no longer; in June it raised its deposit rate to 2.25%, the first increase in nearly three years, because the war has pushed eurozone inflation above 3%, and traders expect further tightening. A wall of new supply confronted with monetary tightening is the textbook recipe for a higher "term premium" — the extra reward lenders demand for locking up money for 30 years during a war, rather than rolling it over at short-term rates. Investors are accordingly demanding more to absorb a record pile of German paper.

The strain is visible in the plumbing. In mid-August a German 10-year auction raised €3.8bn against a target of €6bn, and the syndication of a 30-year bond carried its highest yield since 2011. The paper is being absorbed — but only at a price.

Note what the higher cost is not. This is no threat of default. German public debt stands at about 62.5% of GDP, low by the standards of the G7, and even the finance ministry's projection toward 80% by 2029 would leave Germany near the bottom of the eurozone's borrowing table. The repricing is about price rather than solvency: after years of negative real returns, the 30-year Bund offers its owner roughly a percentage point of real income once German inflation of 2.8% is subtracted. The bond market is doing its job again, demanding compensation for a risk it once waved through.

American investors feel the consequences even if they hold no German paper. Long-dated yields move together across borders, so international bond funds and even domestic funds share the repricing (higher yields depress the price of bonds already held). The money keeps coming all the same: fund-flow data show investors added about $4bn in the past month to TLT, the largest long-dated Treasury ETF, despite falling prices, because the income is finally worth having. That is how a wall of supply is digested — not by panic, but by paying up.

The deepest consequence is institutional. The European Central Bank is tightening into stagnation — the European Commission expects Germany to grow just 0.6% this year, after two years of recession — while the anchor state borrows and spends on a scale unseen outside the pandemic. German fiscal freedom is thus the euro zone's stress test in reverse: the country that once steadied the union is now testing it.

What the experiment is really testing is whether the borrowed money buys growth. Peace in the Middle East would ease oil, inflation and the long end together; thin auctions would signal absorption trouble. If the defence-and-infrastructure splurge revives the German economy, higher yields are simply the price of revival. If it does not, the interest bill compounds with nothing to show for it. The fifteen-year high is therefore not a verdict on German credit. It is the price of a choice Berlin has made — and the beginning of a dearer era for Europe's supposedly risk-free asset, after fifteen years in which investors paid Germany to take their money.