TL;DR. A carry trade borrows money in a currency with a low interest rate and reinvests it in a currency with a higher one, hoping to pocket the rate difference. When the funding currency stays cheap, the trade pays a steady spread. When it suddenly rallies — usually after a central-bank surprise or a volatility shock — leveraged positions unwind together, and the strategy can lose months of profit in a few days.
What a Carry Trade Actually Is
A carry trade is a leveraged bet that the interest-rate gap between two currencies will outweigh any move in the exchange rate between them.
The textbook recipe has three steps:
- Borrow in a currency where short-term rates are low — historically the Japanese yen (JPY) or, after 2015, the euro (EUR).
- Convert the borrowed money into a currency where short-term rates are higher — the US dollar (USD), Mexican peso (MXN), Brazilian real (BRL), or Turkish lira (TRY).
- Park the funds in a short-dated, high-quality instrument: a Treasury bill, a money-market deposit, or a short-dated government bond.
The trader earns the difference between what they pay on the loan and what they earn on the deposit. That spread is called the carry.
Two things make the carry trade interesting and dangerous. First, traders use leverage — often 5x to 20x in FX — to scale a small spread into a meaningful return. Second, the trade carries no directional view on the exchange rate; it only works if the funding currency does not appreciate by more than the spread.
A Worked Example with Real Numbers
Take a $10 million yen-funded carry into US Treasury bills, the cleanest version of the trade.
- Funding: Borrow ¥1.5 billion at the BoJ’s overnight call rate, around 0.75% (the rate the Bank of Japan set on April 28, 2026).
- FX: Convert the ¥1.5 billion into roughly $10 million at the prevailing spot rate.
- Investment: Buy 3-month Treasury bills yielding roughly the middle of the Fed’s 3.50–3.75% target range (set on Dec 11, 2025).
On a one-year horizon, the gross carry is roughly 2.8% on $10 million, or about $280,000 — before fees, financing spreads, and any move in USD/JPY. With 10x leverage, that spread becomes about 28% on the trader’s equity, which is why carry strategies dominate FX trading desks even though the spread itself is modest.
The catch is that the same 10x leverage means a 0.3% strengthening of the yen wipes out a full year of carry. A 3% yen rally erases ten years. And once a few large players start to unwind, the FX move tends to be much larger than 3%.
Why Carry Trades Blow Up
Three forces, often arriving together, make carry trades dangerous:
1. Funding-currency rallies
Low-yielding currencies tend to be the “safe haven” trade when global risk appetite collapses. As the BIS noted in 2007, “at times of heightened global equity and bond market volatility, high-yielding currencies tend to depreciate while low-yielding ones tend to serve as a ‘safe haven'” (BIS Quarterly Review, March 2007). The very moments when you want the carry to keep paying are the moments the FX rate moves against you.
2. The “peso problem”
Academics describe carry returns as picking up nickels in front of a steamroller. The trade earns a small spread most of the time, then occasionally suffers an outsized loss that wipes out years of profit. This is called the peso problem: the rare bad event is large enough that, on a probability-weighted basis, the strategy may not actually have positive expected return — even when it looks profitable in any given year.
3. Crowded positioning and forced unwinds
When everyone is in the same trade, the unwind feeds itself. Margin calls force traders to sell their USD assets and buy back yen to repay the loan. That buying drives the yen higher, triggers more margin calls, and so on. The August 2024 episode — when a surprise Bank of Japan rate decision on July 31, 2024 (see the BoJ policy statement archive) triggered a global selloff in equities and a sharp yen rally — is the canonical recent example.
A Snapshot of Today’s Carry Opportunities
The carry available between currency pairs is set by central banks. The table below shows where the largest funding-vs-target spreads sit right now.
| Central bank | Policy rate | Set on | Role in carry trades |
|---|---|---|---|
| Bank of Japan | ~0.75% | Apr 28, 2026 | Primary funding currency (JPY) |
| European Central Bank (overnight deposit rate, illustrative) | Low-yield bloc | — | Secondary funding currency (EUR), post-2015 |
| Federal Reserve | 3.50–3.75% | Dec 11, 2025 | Target currency at the cleanest end of the risk spectrum (USD) |
| EM central banks (MXN, BRL, TRY, ZAR) | High single-digit to double-digit | — | High-carry but FX-volatile target currencies |
A Short History of Carry-Trade Blowups
The 2008 global financial crisis featured one of the most famous yen-carry unwinds in history. Estimates suggested that by early 2007, around $1 trillion had been staked on yen-funded carry trades (Wikipedia: Carry (investment)). When risk appetite cratered, the yen rallied sharply and the trade collapsed, contributing to the credit crunch.
Iceland’s 2008–2011 crisis is the retail version. Households and small businesses took out mortgages and personal loans denominated in euros and Swiss francs to capture lower foreign rates. When the krona depreciated, those foreign-currency loans ballooned and many defaulted.
The August 2024 episode was the most recent reminder. A surprise Bank of Japan rate decision on July 31, 2024, combined with weaker US data, triggered a global unwind that drove sharp moves in Japanese equities, the yen, and global volatility before stabilizing.
Common Beginner Mistakes
- Confusing the carry with the expected return. Uncovered interest-rate parity says the high-yield currency should depreciate by exactly the rate differential — meaning the expected carry, in theory, is zero. In practice the parity often breaks, which is why the trade exists, but the spread is not a free lunch.
- Ignoring leverage. The unlevered carry is small. Almost all of the headline return number you see in marketing materials comes from leverage — which is also what triggers forced unwinds.
- Treating the “risk-free” leg as actually risk-free. The deposit currency is rarely the issue. The risk lives in the FX rate, not the asset you bought with the borrowed money.
- Underestimating correlation with risk assets. Carry tends to lose when equities lose. It is not a diversifier; it is a leveraged short-vol position dressed up in FX clothing.
Related Concepts to Learn Next
- Uncovered interest-rate parity — the textbook condition that predicts carry trades should not work, and why violations matter.
- FX volatility regimes — why carry strategies perform well in low-vol environments and badly when implied vol spikes.
- The yen as a safe-haven currency — why JPY rallies during risk-off events, the exact opposite of what a yen-funded carry trader needs.
- Forward points and covered interest parity — the FX-forward version of the rate differential, which prices in the carry up front.
Sources
- Bank of Japan, Statement on Monetary Policy, April 28, 2026 (PDF) — current 0.75% overnight call rate target.
- Federal Reserve, Open Market Operations — current 3.50–3.75% federal funds target range (set Dec 11, 2025).
- Bank of Japan, Statements on Monetary Policy archive — full history of BoJ policy decisions including the July 31, 2024 rate hike that triggered the August 2024 unwind.
- BIS Quarterly Review, March 2007 — “Exchange rates and global volatility” — the canonical description of safe-haven dynamics in funding currencies.
- Carry (investment) — Wikipedia — overview of the 2008 yen-carry collapse, the Iceland episode, and the ~$1 trillion peak yen-carry estimate from early 2007.
Disclosure: This article was produced with AI assistance and reviewed before publication. It is for informational purposes only and is not investment advice.