Japan Borrowing Costs Hit 30-Year High as Bond Market Tests Takaichi

Japan’s long-term borrowing costs have climbed to their highest in nearly three decades, with the benchmark 10-year government bond yield reaching 2.85%, a level last seen in 1996, according to a Financial Times-cited explainer published on July 8. The 30-year Japanese government bond yield has moved above 4% this year, close to record highs, the same report said. The sell-off captures a market that has grown visibly impatient with the country’s fiscal trajectory under Prime Minister Sanae Takaichi, who took office in October 2025 and has tied her political project to expansionary spending and tax cuts.

Japan already carries one of the heaviest public debt burdens in the developed world, with gross government debt exceeding 200% of GDP. For years, near-zero policy rates and persistent deflation kept that figure from mattering much to investors. Both pillars are gone. The Bank of Japan has begun raising rates, inflation has stayed above target, and Takaichi’s government has signalled it intends to lean harder on the budget rather than rein it in. The FT-cited jump to a 30-year high in Japanese borrowing costs reflects all three forces converging at once.

The Takaichi Fiscal Blueprint

Takaichi’s signature economic programme is a long-term spending package valued at roughly USD 2.3 trillion over 14 years, paired with a pledge to suspend Japan’s 8% consumption tax on food for two years. The annual revenue from the food tax alone is about ¥5 trillion (€31.5bn), and Takaichi has separately unveiled a stimulus package of roughly ¥21.5 trillion (€115bn), according to reporting on the BoJ’s split decision to hold rates steady. With Japan’s debt-to-GDP ratio near 240%, the highest in the developed world, the prospect of an unfunded tax cut has drawn uncomfortable comparisons to the UK’s 2022 “mini-budget” episode.

Japan’s parliament approved the 2026 budget only belatedly, and the Council on Economic and Fiscal Policy is now reshaping the country’s fiscal anchor. Tokyo is shifting away from a single-year primary balance target toward a medium-term path aimed at stabilising the debt-to-GDP ratio, a framework that aligns Japan with the EU’s medium-term fiscal-structural plans and the UK’s rolling debt-decline horizon. The move is intellectually coherent. It also hands markets a longer horizon over which to doubt the government’s discipline. The food tax cut is, in Takaichi’s own framing, a “temporary bridge” until a refundable tax-credit system can be designed. The bridge, in market terms, is what investors are paying for.

Why the Long End Is Doing the Damage

The most punishing moves have been at the very long end of the curve. On January 20, 2026, Japan’s 40-year government bond yield touched 4.213%, the highest level since the 40-year maturity was introduced. The 10-year JGB yield jumped more than 10 basis points the same session to 2.38%, the highest level since 1999, and the 20-year tenor surged roughly 22 basis points to 3.47%, according to the CNBC report on Japan’s 40-year yield touching a record 4.213%. The 30-year bond yield rose almost 30 basis points in the same session to roughly 3.9%, a level that stood as the highest on record at that point.

Long-dated yields are where investors price duration risk, and the super-long end has been the most exposed. As one strategist put it, ultra-long JGB yields are being pushed higher by both a structural supply-demand imbalance and a fresh repricing of term and risk premium as markets absorb a more expansionary fiscal stance and persistent inflation. That repricing has revived a familiar pattern in Japanese markets, weaker yen, stronger equities, weaker JGBs, that the strategist named the classic “Takaichi trade.”

• 2.85% on the 10-year JGB, highest since 1996.
• 4.213% on the 40-year JGB, a record since the maturity was introduced.
• 30-year JGB cleared 4% earlier in 2026, close to record highs.
• Gross government debt above 200% of GDP; debt-to-GDP near 240% on broader measures.
• Oxford Economics puts 10-year JGB around 2.7%, up from 2.1% in March 2026.

The ‘Takaichi Trade’ Returns

The phrase has become shorthand for a specific combination: weaker yen, stronger Nikkei, higher long-dated JGB yields. It first surfaced in late 2025 when Takaichi’s policy signals pointed toward looser fiscal policy, then stabilised, and returned with force after her January call for a snap February 8 election.

This has revived the classic ‘Takaichi trade’ dynamic of stronger Nikkei, weaker JGBs and yen.

The quote comes from Masahiko Loo, senior fixed income strategist at State Street Investment Management. The repricing has technical and sentiment echoes rather than signalling structural distress, Loo added, and the yield curve is likely to remain steep through the first half of this year before stabilising as bond issuance patterns adjust and domestic banks return as buyers. Oxford Economics agrees on direction if not on speed: in a June 8 briefing, the consultancy lifted its 10-year JGB forecast to 2.8% at end-2026, up from 2.5%, citing higher inflation and concerns about Japan’s fiscal expansion.

The 10-year JGB stood around 2.7% at the time of that note, having risen sharply from 2.1% in March, fuelled by concern about Japan’s more aggressive fiscal stance and the global repricing of yields driven by real rates and rising inflation expectations. A slight retreat in the 10-year yield reflected a June supplementary budget that came in smaller than markets had anticipated. Oxford Economics expects the policy direction to clarify by around the end of June and has not ruled out further revisions.

BoJ Walks a Tightrope

The Bank of Japan is now operating between two audiences. One wants higher rates to normalise policy after decades near zero and to defend a yen that has touched a 40-year low. The other wants the BoJ to slow its exit, because the cost of that exit is showing up in long-dated yields the central bank itself helped suppress for years. The BoJ raised its key policy rate to 1% last month, the highest in three decades. It also recently indicated that it would slow the pace at which it reduces its bond purchases, signalling a willingness to stabilise the market if necessary. That mix, more rate hikes plus slower balance-sheet runoff, is what Takaichi’s team would prefer. It is also what global investors parsing Japan’s debt trajectory are most wary of.

The Spillover Beyond Japan’s Borders

Japan is the largest foreign holder of US government debt. As of November 2025, Japanese entities held about $1.2 trillion in US Treasury securities. That footprint is why the world’s bond desks are watching Tokyo’s fiscal debate as closely as Washington’s tariff announcements.

The basic problem in the global bond market, in the words of Ed Yardeni, president of Yardeni Research, is that major governments of the major economies are running large deficits and have accumulated a great deal of debt. Investors, Yardeni added, are starting to demonstrate that they are not happy about that. If Japanese yields keep climbing, Japanese investors are more likely to stay home and buy their own bonds rather than US Treasuries, which would put upward pressure on US yields in turn. Strategists have separately warned that Europe’s large holdings of US assets could complicate global capital flows, with Deutsche Bank estimating European countries hold $8 trillion in US bonds and equities, about twice as much as the rest of the world combined.

• Capital repatriation pressure on US Treasuries if JGB yields stay attractive at home.
• Higher global long-end yields as Japan resets the term premium other sovereigns price off.
• Sovereign debt scrutiny spreading to other heavily indebted advanced economies.

Domestically, the deeper concern is structural. Bruegel researchers wrote in a recent policy note that, in realistic growth scenarios, Japan’s debt will not stabilise on its own. The think tank’s recommendation is that stabilising the debt will require sustained primary budget surpluses and stronger institutions, including an independent fiscal council. Japan’s debt sustainability, Bruegel added, hinges not only on macroeconomic conditions but also on the credibility of growth forecasts and the government’s ability to maintain fiscal discipline over time, the same warning that Japan’s debt won’t stabilise on its own now echoed in Tokyo’s own market reaction. The political backdrop adds another layer: Takaichi’s election-cycle trade-offs and external pressure from tariff fights, including Trump’s 25% tariff move on Japan and South Korea, leave her cabinet with less fiscal headroom at exactly the moment bond investors are demanding more of it.

Frequently Asked Questions

What is driving Japan’s borrowing costs to a 30-year high?

Investor concern over Prime Minister Sanae Takaichi’s expansionary fiscal programme, valued at roughly USD 2.3 trillion over 14 years, combined with the Bank of Japan’s gradual exit from ultra-loose monetary policy and persistent above-target inflation. The 10-year JGB yield hit 2.85%, its highest level since 1996.

How high have JGB yields actually climbed?

The 10-year JGB yield has reached 2.85%, its highest since 1996. The 30-year yield has cleared 4% this year, close to record highs. On January 20, 2026, the 40-year JGB yield touched 4.213%, the highest level since that maturity was introduced.

What is the ‘Takaichi trade’?

The term describes the combination of a weaker yen, stronger Japanese equities, and higher long-dated JGB yields that tends to follow policy signals from Prime Minister Takaichi. Strategists at State Street Investment Management and Oxford Economics both use the phrase to describe the pattern that re-emerged after Takaichi announced a snap February 2026 election.

Why does this matter outside Japan?

Japan is the largest foreign holder of US government debt, with about $1.2 trillion in US Treasuries as of November 2025. Higher JGB yields can pull Japanese capital back home, putting upward pressure on US and other long-end yields and tightening global financial conditions.

What is the Bank of Japan doing in response?

The BoJ raised its key policy rate to 1% last month, the highest in three decades, while signalling that it will slow the pace at which it reduces its bond purchases. The mix, more rate hikes plus slower balance-sheet runoff, is meant to normalise policy without destabilising the long end of the JGB curve.