Japan’s Zero Interest Rates: NIRP, Carry Trade, and Exit

Japan held its policy interest rate at or near zero for roughly a quarter century, first pushing it to effectively zero in 1999 and then below zero in 2016, before finally lifting off in March 2024. As of early 2026 the Bank of Japan’s policy rate sits at 0.75%, with further hikes expected. Japan’s zero interest rates were the longest experiment of their kind in any major economy, and the effects reached from Tokyo bank branches to Wall Street trading desks.

Why Japan Went to Zero in the First Place

The policy was a response to the collapse of one of the largest asset bubbles in modern history. In the late 1980s, speculative buying drove Japanese stocks and real estate to extraordinary levels. When the bubble broke, equity prices fell roughly 60% between late 1989 and August 1992, and land values ultimately dropped about 70% by 2001. Banks were left holding huge portfolios of non-performing loans, and the economy slid into the stagnation and deflation now known as the Lost Decades.

Deflation is dangerous because it feeds on itself. When prices keep falling, households and businesses put off spending, expecting things to be cheaper next month. That delayed spending pushes prices down further. Japan’s consumer prices drifted sideways or declined for years, and in January 2013 the BoJ set an explicit 2% inflation target to try to anchor expectations in the other direction.1Bank of Japan. Price Stability Target of 2 Percent

Demographics made the fight harder. Japan’s working-age population began shrinking in the early 1990s, and IMF research found that aging generates “substantial deflationary pressures” on its own, through weaker growth potential and falling land prices.2International Monetary Fund. Is Japan’s Population Aging Deflationary? The BoJ was pushing against a structural headwind that monetary policy alone could not undo.

How ZIRP and NIRP Actually Worked

In February 1999, the Bank of Japan announced it would push the uncollateralized overnight call rate, its main policy tool, “as low as possible,” initially targeting around 0.15% before driving it lower.3Bank for International Settlements. Japanese Monetary Policy: 1998-2005 and Beyond This was the Zero Interest Rate Policy, or ZIRP. The idea was to make short-term funding nearly free for commercial banks, so they would pass cheap credit through to businesses and households. The BoJ’s policy board described the aim as keeping rates at “virtually zero” until deflation concerns were dispelled.4Bank of Japan. The Transmission Mechanism of Monetary Policy Near Zero Interest Rates: The Japanese Experience

More than fifteen years of near-zero rates still failed to lift inflation to 2%, so in January 2016 the BoJ escalated to a Negative Interest Rate Policy, or NIRP.5International Monetary Fund. Achieving the Bank of Japan’s Inflation Target Under NIRP, a -0.1% rate applied to a specific slice of the reserves commercial banks held at the central bank. Banks were, in effect, charged a fee for parking excess cash at the BoJ instead of lending it out.

The negative rate did not apply to all reserves, which would have gutted bank profitability overnight. Instead, the BoJ used a three-tier structure for banks’ current account balances.6Bank for International Settlements. Japan A “basic balance” earned a positive rate, a “macro add-on” tier earned zero, and only the marginal “policy-rate balance” was hit with the -0.1% penalty. The BoJ adjusted the boundaries between tiers roughly every three months so the negative-rate portion stayed small enough not to bleed banks dry but large enough to change behavior.

What It Did to Banks and Insurers

Banks earn money on the spread between what they charge borrowers and what they pay depositors. When lending rates sit near zero and deposit rates cannot realistically go negative for retail customers, that net interest margin gets crushed. Japanese banks operated under this structural squeeze for years, and financial stocks fell sharply when NIRP was announced in 2016.

Banks adapted by looking abroad. Major Japanese banks expanded foreign lending, particularly in emerging Asia where yields remained attractive. At home, institutions pivoted toward fee-based services like wealth management to replace lost interest income. These were survival strategies rather than growth stories.

The recovery, once rates started rising, was dramatic. In fiscal year 2024 (ending March 2025), major financial groups posted net income of about 4.5 trillion yen, up 33.2% from the prior year, and regional banks saw a 36.8% jump. Interest rate spreads on loans widened at both major and regional banks as lending rates rose faster than funding costs.7Bank of Japan. Financial Results of Japan’s Banks for Fiscal 2024

Life insurers had it worse. During the high-rate 1980s, they sold long-term policies with guaranteed returns of 4% to 6%. When portfolio yields fell from around 6.5% in 1990 to about 2% by 2000, a “negative spread” of roughly two percentage points opened up between what insurers had promised and what they could earn. Between 1997 and 2001, seven Japanese life insurance companies became insolvent, the first such failures since World War II. Survivors moved heavily into foreign bonds, particularly U.S. dollar debt, and expanded into markets like Australia and the United States.

Savers, Borrowers, and Housing

For anyone living on savings, the era was punishing. Returns on bank deposits and Japanese government bonds sat near zero for years, hitting retirees especially hard. Many households kept accumulating cash anyway. When prices are falling, zero-yield cash still gains purchasing power over time, and decades of uncertainty made risk-taking feel unsafe.

Borrowers were the mirror image. Mortgage rates fell to historic lows, making housing finance extraordinarily cheap. That stabilized real estate for much of the period and eventually helped fuel a price surge. Japanese land prices rose at their fastest rate in 15 years heading into 2023, and new condominium prices in central Tokyo doubled between March 2022 and March 2023, with the pressure spreading to regional cities.

The split between savers and borrowers was one of the sharpest distributional effects of the policy. Older households who had saved for retirement watched their asset income evaporate. Younger buyers locked in housing debt at rates that would have seemed impossibly low a generation earlier.

Zombie Companies and the Productivity Drag

Free money has a side effect: it keeps failing businesses alive. When borrowing costs approach zero, firms that could not otherwise service their debts can roll over loans indefinitely. Economists call these “zombie companies,” and Japan became the textbook case. By 2010, nearly one in five Japanese firms qualified.

The damage extended beyond the zombies themselves. Research on Japanese manufacturing found that without zombie lending, aggregate productivity growth would have been roughly one percentage point higher per year during the 1990s. Zombie firms held onto workers and capital that more productive firms could have put to better use, and the labor misallocation effect accounted for nearly all of the negative labor reallocation observed during the decade.8ScienceDirect. Resource Reallocation and Zombie Lending in Japan in the 1990s In 2024, the number of Japanese zombie companies began edging down for the first time in seven years, coinciding with the return to positive rates.

The Yen Carry Trade and the August 2024 Crash

Japan’s near-zero rates reshaped global finance through the yen carry trade. The mechanics are simple: borrow yen cheaply, convert to a higher-yielding currency like the dollar, invest in assets paying a much better return, and pocket the difference. With Japanese rates near zero and U.S. rates above 5% at their peak, the gap made the trade highly profitable for banks, hedge funds, and institutional investors.9AMRO (ASEAN+3 Macroeconomic Research Office). Analytical Note: Understanding Currency Carry Trades: The Yen Carry Trade and Its Impact on ASEAN+3 Economies

Carry trades are leveraged bets on stability. They work as long as the rate gap holds and the yen does not strengthen sharply. Going into mid-2024, yen carry positions were estimated at roughly ¥40 trillion (about $250 billion), though data gaps likely made the true figure higher.10Bank for International Settlements. The Market Turbulence and Carry Trade Unwind of August 2024

The risks came due in August 2024. After the BoJ raised its rate to 0.25% in July on a more hawkish tone than markets expected, weak U.S. jobs data the following week set off a rush to unwind yen positions. On August 5, the Japanese TOPIX index fell 12% in a single day, and the Nikkei volatility index spiked to levels normally seen only in full-blown crises. The damage spread globally: the S&P 500 dropped 3%, the MSCI Asia Pacific Index had its worst day in a year, and Bitcoin and Ethereum lost up to 20% as traders facing margin calls sold whatever they could.10Bank for International Settlements. The Market Turbulence and Carry Trade Unwind of August 2024 A modest BoJ hike had triggered a chain reaction that moved trillions in global market value within days.

The Exit From Zero

The BoJ’s March 2024 decision to end negative rates was historic. The central bank raised the policy rate from -0.1% to a range of 0% to 0.1%, scrapped Yield Curve Control (the policy that had capped 10-year government bond yields), and said QQE with YCC and negative rates had “fulfilled their roles.”11Bank of Japan. Changes in the Monetary Policy Framework

Hikes have come in steady steps since:

The BoJ’s justification rests on what it calls a “virtuous cycle” between wages and prices. Spring wage negotiations (shunto) delivered increases above 5% for a third consecutive year in 2026, the kind of sustained wage growth Japan had not seen in decades. Core inflation has been uneven, moderating to 1.6% in February 2026, though the BoJ forecasts an average of 1.9% for fiscal 2026 and projects core-core inflation at 2.2%. Analysts expect the policy rate could reach 1% by mid-2026, with the pace depending on inflation data, yen movements, and global conditions.

For banks, normalization has already delivered tangible results, with net income rising sharply and loan spreads widening for the first time in years. For savers, positive deposit yields are returning after a generation of earning nothing. For borrowers, the era of essentially free money is ending, though rates remain low by any historical or international standard. And for global markets, every BoJ meeting now carries weight it has not had since the 1990s.