The weak yen and your clients
October 21, 2026 · Michael Lawton · Based on our flash note The weak yen is already in the numbers
The 30-second version
The yen is near 158 per dollar, still weak even after Japan's central bank raised rates in September, because the US Federal Reserve raised rates too. For long-term diversified portfolios this is a currency story, not a reason to change allocations: it mainly affects how Japanese and international holdings translate back into dollars. Expect client questions if the Bank of Japan moves on October 30 or in December.
What clients will ask
“Why doesn't my Japan or international fund match the Nikkei number on the news?”
The Nikkei is quoted in yen. A US investor's fund is converted back to dollars, so when the yen weakens, the dollar return is lower than the headline. The companies didn't do worse; the currency did.
“Should we get out of Japan?”
Currency swings are a normal part of owning international stocks, and they tend to even out over long periods. Many Japanese companies actually earn more when the yen is weak, because they sell abroad. One currency move isn't a reason to abandon diversification.
“Does this affect my plan?”
For a diversified long-term portfolio, not meaningfully. The main everyday effect is on travel: a weak yen makes a trip to Japan cheaper for Americans.
What it means for portfolios
The yen matters most through how clients hold Japan, not whether they hold it.
| Holding type | Effect of a weak yen | Effect if the yen strengthens |
|---|---|---|
| Unhedged Japan or international developed funds | Dollar returns trail local returns | Currency adds to dollar returns |
| Currency-hedged Japan funds | Currency effect removed; hedging also earns roughly the US–Japan rate gap | The hedge gives up the currency gain |
| US large caps with big Japan sales | Yen sales translate into fewer dollars | A small tailwind |
- International developed funds are exposed. Japan is one of the larger country weights in typical developed ex-US indexes; check each fund's fact sheet for the exact share.
- Japan's market leans toward exporters. Autos, machinery and electronics are big index weights, and their earnings tend to rise when the yen falls, which partly offsets the currency drag in an unhedged fund.
- No action implied. This is a reason to know which funds are hedged and to explain the difference, not to rotate.
What to watch next
| Signal | If it happens | Expect clients to call about |
|---|---|---|
| BOJ decision, Oct 30 | A surprise hike (markets price only about 10% odds) | A sharp yen jump and a dip in Japanese exporter stocks |
| BOJ decision, Dec 18 | A hike, as most expect | Little; largely priced in |
| Another Fed hike | The rate gap widens; the yen tests 160 | “Why are my international funds lagging again?” |
| Government intervention | Japan buys yen, as it did with the US Treasury in late July | A sudden one-day yen spike in headlines |
Client-ready paragraph
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You may have seen headlines about the Japanese yen, which is trading near its weakest level against the dollar in decades. The main reason is simple: interest rates in the US remain much higher than in Japan, which pulls money toward the dollar. For investors, this mostly affects how international holdings translate back into dollars. It can make Japanese stock returns look lower for US investors than the headlines suggest, even when the underlying companies are doing well. Many large Japanese companies actually benefit from a weak yen because they sell their products around the world. We don't see this as a reason to change a long-term, diversified plan, but we're watching it closely and are happy to talk through how it affects your portfolio.
The analysis behind it
Why the yen is weak. The BOJ raised its rate to 1.25% on September 18, but the Fed raised to 3.75–4.00% on September 16, so the gap of roughly 2.5 to 2.75 points barely moved. Carry trades keep pressure on the yen; intervention risk caps how far it falls.
What's already priced in. Toyota raised its full-year operating profit forecast to ¥3.4T and now assumes ¥160 per dollar, weaker than today's ~158. Exporters' weak-yen benefit is largely in their guidance already.
What would prove us wrong. The Fed keeps hiking and the yen breaks through 160; the BOJ pauses past December; an oil spike; or higher US tariffs on Japanese autos. Read the full research note →
Sources
- Trading Economics: Japanese yen
- Bloomberg via The Edge: BOJ leans against back-to-back hike
- FXStreet: BoJ to leave rates steady
- Khaleej Times: US Fed raises rates
- Toyota Q1 FY2027 presentation (Aug 4, 2026)
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