- On 1 December the Bank of Japan governor signalled that rates might rise that same month.
- The yield on Japanese debt hit multi-year highs.
- It helps to know whether a portfolio depends on cheap financing in another currency and what would happen with faster rate rises than expected.
On 1 December 2025, the governor of the Bank of Japan signalled that the central bank might raise interest rates that same month. The market reaction was immediate: the yield on Japanese debt hit multi-year highs. Although Japan may seem far from many everyday decisions, its rates and its currency are an important cog in global financial markets. That importance stems from the size of its economy and the amount of investment that moves in yen around the world.
For years, Japan has been the example of an economy with extraordinarily low rates. Any sign of change is therefore followed with particular attention: not only for what it means for its citizens and companies, but for what it implies for capital flows and for the assets that depend on them, in Europe too. For a European investor, understanding these movements is useful even without holding a single yen.
A signal from Tokyo
A signal like that, pointing to a possible rate rise in the same month, is the kind central banks give to prepare markets, and they responded without delay, with the yield on Japanese debt at multi-year highs.
Central banks rarely surprise on purpose; they prefer to give notice so that markets adjust in an orderly way. That is why a governor’s words can be as important as the decision itself. When the notice is clear, prices move beforehand, and the later decision tends to do no more than confirm what is already priced in. For those who follow the news, the lesson is that the relevant information usually arrives before the decision.
The end of cheap money
The end of cheap Japanese money remained a risk for investments financed in yen. When rates in Japan rise, borrowing in yen to invest in other markets becomes less attractive, and those who had done so may be forced to unwind positions, with effects on other assets.
Unwinding a position financed in yen means buying yen to repay the debt, which tends to strengthen the Japanese currency and to put downward pressure on the assets that had been bought. When many participants do so at once, the movement accelerates. It is a mechanism seen on other occasions, and it explains why a change in rates in Tokyo can be felt in distant markets. That is why financial markets are said to be connected by channels that are not always visible.
The shadow of 2024
The precedent of August 2024 was present in every analysis. It is worth knowing whether a portfolio or a strategy depends, even indirectly, on cheap financing in another currency, and what would happen in a scenario of faster rate rises than expected.
For a private investor, the practical question is whether the funds or products held use leverage or currency financing, and whether their managers have planned for stress scenarios. For a company, the question is whether its financing depends on a currency whose cost may change. In both cases, understanding the risk is more useful than trying to guess the date of the next decision. An adviser can help to review that exposure calmly and to decide whether it is worth reducing it.
What sounds distant, like rates in Japan, can reach a local portfolio.
This article is general information. It is not legal, tax or investment advice, and it does not take anyone’s particular circumstances into account.
