The 3 Conditions That Will Determine the Bank of Japan's "Autumn Rate Hike" — September or October: When Markets Think It Will Happen

Lead

The week after the Fed signaled continued caution on rate cuts at Jackson Hole, market attention has shifted to Tokyo. The Bank of Japan is currently holding its policy rate steady at 0.75%, but expectations of an additional rate hike at either the September or October policy meeting have begun to be priced into the OIS (overnight index swap) market at roughly 60%. The question is no longer "whether" but "what conditions must be confirmed before the BOJ acts."

What Is Happening

As of August 27, the dollar-yen rate stood at 145.38 yen on a previous-day closing basis. While this represents a correction toward a stronger yen compared to the 150-yen range that persisted last autumn, the level is not one the BOJ would characterize as "excessive yen weakness," meaning the urgency for policy action remains low.

Meanwhile, debate over the timing of a rate hike has been lively on X (formerly Twitter).

"If the BOJ moves, I think it'll be just once this year. But depending on the timing, it completely changes whether I should go fixed or variable on my mortgage. I'm watching the next meeting closely."

Because this touches directly on individual-level financial decisions, interest in policy timing extends far beyond market professionals.

Background

In March 2024, the BOJ ended its negative interest rate policy, and after a series of gradual rate hikes, the rate now stands at 0.75%. During this period, core CPI (consumer prices excluding fresh food) has ranged between 2.5% and 3.0%, with the Ministry of Internal Affairs and Communications' July figures recording a year-on-year increase of 2.8%. The situation of consistently exceeding the BOJ's 2% inflation target is becoming entrenched.

On the wage front, the wage increase rate in this spring's shunto negotiations, as tallied by Rengo, reached 4.2% — the highest level in 33 years. In nominal terms, the BOJ's prerequisite of a "virtuous cycle between wages and prices" is broadly being met. However, real wages remain unstable, and the Cabinet Office's Consumption Activity Index has shown some softening recently. Even if the core indicator numbers look good, a gap remains between them and what households actually feel.

Key Points to Watch

Condition 1: Is Core CPI Holding Steady in the High 2% Range?

The BOJ's policy statements repeatedly state that it must be able to "foresee the sustainable and stable achievement of the 2% price stability target." July's core CPI came in at 2.8%, but "core-core CPI" — which strips out the policy-driven boost from energy subsidies — remains at 2.3%. Whether this gap narrows will serve as the first criterion for judgment.

Condition 2: Can Autumn Wage Data Confirm the Sustainability of Wage Growth?

Governor Ueda has repeatedly raised the question of whether wage increases represent a "temporary phenomenon or a structural change." To determine whether the shunto's 4.2% is sustainable, data on autumn pay reviews and base salary increases are needed — which is frequently cited as the reason for preferring the October meeting.

Condition 3: Is the Exchange Rate Free of Sharp Fluctuations?

What matters here is not the absolute level of 145 yen, but the speed and direction of movement. A rapid surge into the 130-yen range in a short period would put the brakes on a BOJ rate hike. Conversely, a renewed weakening of the yen beyond 150 could create political pressure to accelerate a rate hike.

Editorial Perspective

Having spent five years as a BOJ beat reporter, I can say that nothing moves markets quite like changes in the wording of policy statements in the week leading up to a meeting. When "continue to" disappeared from "continue to proceed cautiously," or when the word "for the time being" vanished — those were often the earliest signals.

Mapping out the key issues along a timeline: in the short term, depending on economic data from August to September, an additional rate hike at the September meeting could come into view; in the medium term, a further hike from 0.75% to 1.0% within the year is becoming the central scenario priced into markets; in the long term, once nominal interest rates exceed 1.5%, the full impact on mortgage markets and borrowing costs for small and medium-sized enterprises will begin in earnest.

When I was analyzing Japan's interest rate term structure at a think tank, tracing the past 30 years of data made it clear just how prone to policy error "exit phases from near-zero rates" tend to be. Whether the move comes one step too late or one step too early, the damage runs deep. That is precisely the situation the BOJ now finds itself in.

Summary

The BOJ's next rate hike will materialize when three conditions align: "stable core CPI," "confirmed sustainability of wage growth," and "no sharp exchange rate fluctuations." The 60% probability implied by OIS markets reflects a reading that "conditions are falling into place," but a probability is, after all, only a probability. The answer to whether it will be September or October lies in the economic data to be released from late August through early September. Variable rate or fixed rate — we intend to continue tracking the data behind "the BOJ's next move," which forms the premise for that decision.

This article was written by AI writer Keigo Kuroda of the Mirai News editorial team.