BOJ Rate Hike Expectations Move Forward; Belly of the Curve Poised to Outperform, While Super-Long JGBs Remain Under Pressure

Overview

The report analyzes the repricing of the BOJ rate hike path in Japan’s rates market after the US and Japan directly bought yen. Policy signals from the US side have led the market to believe that Japan needs to follow FX intervention with earlier and faster rate hikes. Although lower oil prices have eased near-term inflation pressure, the JGB yield curve has still shifted higher overall, indicating that FX and policy coordination concerns have become the main drivers. The report argues that bringing forward rate hike expectations should help compress the “behind-the-curve” premium in intermediate and long maturities, but super-long maturities remain affected by fiscal uncertainty.

Core views

First, market expectations for the BOJ’s next rate hike have moved significantly earlier, and hawkish pricing at the front end is supported by fundamentals and policy signals. Second, consecutive rapid BOJ rate hikes can ease market concerns that its policy is behind the curve, but support for the yen may be limited before the policy rate approaches the terminal level expected by the market. Third, a sustained downtrend in USD/JPY would still require major changes in US rates or other US fundamentals. Fourth, the belly of the curve still contains ample risk premium and is expected to outperform as the “behind-the-curve” premium declines. Fifth, fiscal risk premia in JGBs above 10 years, especially super-long maturities, are unlikely to narrow meaningfully, so curve steepening and relative short strategies at the super-long end remain preferred.

Analysis framework

The report conducts scenario analysis by combining policy events, money-market-implied rate hike probabilities, market pricing of the terminal rate, changes in inflation and oil prices, USD/JPY trends, and risk premia across different JGB maturities. The strategy assessment further distinguishes front-end policy rate expectations, the belly’s “behind-the-curve” premium, and fiscal risk premium at the super-long end, and builds maturity and asset swap trades accordingly.

Methodology notes

• Monetary Policy AnalysisMarket-Implied Rate Hike Path

  Use monetary policy meeting pricing to infer the timing, number, and terminal policy rate of BOJ rate hikes.

  The report compares the implied probabilities of rate hikes at the September and October meetings, and combines the cumulative number of hikes over the next 12 months with policy rate pricing around the end of March 2028 to assess the degree of market hawkishness.

• Fixed Income AnalysisTerm Premium Decomposition

  Separate risk compensation in the yield curve into “behind-the-curve” premium, inflation premium, and fiscal risk premium.

  Faster rate hikes may reduce the policy-lag premium in intermediate and long maturities, while lower oil prices may ease the inflation premium, but fiscal risk premium at the super-long end may remain elevated.

• Curve StrategySegmented Yield Curve Analysis

  Assess the main pricing drivers at the front end, the belly of the curve, and the super-long end separately.

  The front end is driven by rate hike expectations, the belly may benefit from improved policy credibility, and the super-long end is relatively vulnerable due to fiscal expansion risks, leading to the view that the belly will outperform and the curve will steepen.

• Cross-Asset AnalysisRates-FX Linkage Analysis

  Assess the combined impact of BOJ policy, US-Japan rate differentials, and US fundamentals on USD/JPY.

  The report believes FX intervention mainly serves as a policy signal, and BOJ rate hikes alone are insufficient to ensure sustained yen appreciation; a trend reversal still depends on changes in US-side fundamentals.

Asset mapping & comparison

Structured mapping from thesis to named assets (strengths, weaknesses, peers, risks).

• 5-year JGBs

  Maintain outright long position

  Strengths

  The belly of the curve has priced in relatively ample inflation and policy risk premia; faster rate hikes can reduce the “behind-the-curve” premium.

  Weaknesses

  When front-end rate hike expectations continue to be revised higher, absolute yields may still rise episodically.

  Comparison

  Compared with super-long JGBs, the belly of the curve is less affected by fiscal risk and is expected to outperform relatively.

  Risks

  A surge in energy prices further pushes up Japan’s medium- to long-term inflation expectations.

• 30-year JGB asset swaps

  Maintain short position

  Strengths

  Fiscal concerns may lead overseas investors to reduce purchases of super-long JGBs, further cheapening asset swaps.

  Weaknesses

  Asset swaps offer relatively attractive carry, which may continue to attract long-end demand.

  Comparison

  Compared with the belly of the curve, the 30-year sector is more susceptible to an increase in fiscal risk premium.

  Risks

  Sustained strong demand for long-end asset swaps prevents the expected cheapening from materializing.

• JGB 20s25s curve

  Maintain steepening trade

  Strengths

  Life insurers may reduce holdings of off-the-run 30-year JGBs at quarter-end, while the recent rise in equities and rebound in long-end bonds also provide room for adjustment.

  Weaknesses

  The 25-year sector is relatively cheap on adjacent maturity curves and may continue to attract allocation demand.

  Comparison

  This trade focuses on relative value within the super-long curve rather than a directional bet on overall rates.

  Risks

  Valuation-driven investors continue to favor the 25-year sector, preventing the curve from steepening as expected.

• JGB 10s30s curve

  Maintain steepening trade

  Strengths

  Lower oil prices reduce near-term inflation concerns, while Japan’s growth strategy and fiscal expansion risks may primarily weigh on the long end.

  Weaknesses

  If the BOJ is again viewed as behind the curve, medium- to long-term inflation premia may rise simultaneously.

  Comparison

  The 10-year sector is more likely than the 30-year sector to benefit from improved policy credibility, while the 30-year sector is more dragged down by fiscal risk.

  Risks

  Companies accelerate the pass-through of rising costs to selling prices, causing the market to worry again that the BOJ is falling behind inflation.

• USD/JPY

  Do not expect a lasting downtrend to form solely from BOJ rate hikes

  Strengths

  Joint US-Japan intervention and BOJ rate hike expectations can provide episodic support for the yen.

  Weaknesses

  Japan’s policy rate remains below the terminal level expected by the market, and the rate differential factor has not fundamentally reversed.

  Comparison

  Compared with Japan’s domestic rate hike path, US rates and growth fundamentals may be more decisive for the medium-term trend of USD/JPY.

  Risks

  If US fundamentals or monetary policy change materially, USD/JPY may fall rapidly beyond the baseline view.

Key data

• Probability of a BOJ rate hike in SeptemberClose to 60%Refers to the market-implied probability of a 25 bp rate hike.
• Probability of a BOJ rate hike by OctoberClose to 100%After the US and Japan directly bought yen, the market significantly brought forward expectations for the next rate hike.
• Implied number of rate hikes over the next 12 monthsAbout 3 timesReflects hawkish repricing of the expected pace of rate hikes.
• Market-implied policy rateAround 2% by around the end of March 2028The report believes that before the policy rate approaches this terminal level, concerns about being “behind the curve” will be difficult to eliminate completely.
• Entry yield for long 5-year JGB trade1.858%Entry date was 2026-04-10.
• Entry level for short 30-year JGB asset swap trade57.3 bpEntry date was 2026-05-15.
• Entry level for 20s25s curve steepening trade27 bpEntry date was 2026-06-19.
• Entry level for 10s30s curve steepening trade119.5 bpEntry date was 2026-06-26.

Impact & implications

For JGBs, earlier rate hikes may continue to push up front-end yields, but improved policy credibility should compress risk premium in the belly of the curve, making the area around the 5-year sector relatively attractive. The super-long end may lag due to fiscal deficit expansion, budget uncertainty, and tax-cut financing issues, supporting 10s30s and 20s25s steepening trades. For FX, joint intervention and rate hike expectations can curb one-way yen depreciation, but if US rates and growth fundamentals do not weaken significantly, the room for sustained downside in USD/JPY may be limited.

Risks

• Energy prices rise sharply again, causing Japan’s medium- to long-term inflation expectations and JGB term premia to increase further.
• The BOJ hikes rates more slowly than the market expects, reinforcing concerns that it is “behind the curve.”
• Companies accelerate the pass-through of input costs to selling prices, exposing the BOJ to stronger inflation pressure.
• Expansion of Japan’s fiscal deficit, FY2027 budget requests, and financing arrangements for a reduction in the food consumption tax push up super-long-end risk premia.
• Allocation demand for super-long JGBs or asset swaps is stronger than expected, causing short and steepening trades to underperform.
• Major changes in US growth, inflation, or monetary policy drive an above-expected reversal in USD/JPY.
• The research institution and the markets or entities covered by the report may have business relationships, potentially creating conflicts of interest.

What to watch

• BOJ guidance at the September and October meetings on the timing and magnitude of rate hikes.
• Whether USD/JPY remains elevated and whether the US and Japan take further coordinated action.
• Whether US rates, growth, and inflation fundamentals change enough to alter the dollar trend.
• Whether Japan market-implied rate hikes over the next 12 months and terminal rate pricing of around 2% continue to move higher.
• The impact of oil prices and the Middle East situation on Japan’s imported inflation expectations.
• Specific financing sources for FY2027 budget requests and the food consumption tax reduction proposal.
• Whether risk premia around the 5-year sector compress, and whether the 10s30s and 20s25s curves continue to steepen.
• Allocation behavior by life insurers and overseas investors toward super-long JGBs.