Japan Weighs ¥70–80 Trillion Defense Plan as Funding and Equipment Costs Draw Scrutiny

A larger military budget, with a larger bill to explain

Japan's government and ruling coalition are considering spending ¥70 trillion to ¥80 trillion on defense over five years beginning in April 2027, a sharp increase that would bring new purchases, rising equipment costs and the question of who pays into the same political debate.

The proposed total, equivalent to roughly $457 billion to $508 billion, compares with about ¥43 trillion under the current program, which began in fiscal 2023. Prime Minister Sanae Takaichi is pushing to strengthen Japan's military capabilities as the government prepares to revise its three main security documents toward the end of the year.

Two people familiar with the discussions described the spending range. One said the final amount could settle in the middle to upper part of the ¥70 trillion range, while questioning whether even that would meet Japan's needs given the security environment in East Asia. The Defense Ministry declined to comment.

The amount, equipment mix and funding arrangements remain under discussion between the government and its coalition partners. The debate also includes pressure from the United States for greater spending, business opposition to a possible corporate tax increase and scrutiny of expensive equipment already ordered.

What would ¥70 trillion to ¥80 trillion mean?

The proposed range would add ¥27 trillion to ¥37 trillion to the current five year allocation. Calculated against ¥43 trillion, that represents an increase of about 63% to 86%. The upper end comes close to doubling the existing program.

Spread evenly across five years, the proposal would average ¥14 trillion to ¥16 trillion annually, compared with ¥8.6 trillion for the current allocation. Actual annual budgets would depend on delivery schedules, contracts and government decisions rather than an equal division.

Japan's current program was itself a major expansion. When the government adopted it at the end of 2022, it increased planned spending from an initial ¥27.5 trillion to roughly ¥43 trillion. The latest discussions would therefore build another substantial increase on top of an already enlarged budget.

The dates also matter. The current program runs through fiscal 2027, ending in March 2028, while the proposed period would begin in April 2027. The two periods overlap by one fiscal year, placing the next spending framework inside the final year of the existing one.

Drones, missiles and the cost of a weaker yen

Large purchases of drones are among the possible uses for the new money, according to one person familiar with the discussions. No quantities or specific drone models were identified.

Drones are aircraft operated without a person aboard. Depending on their design, they can gather information, watch an area or carry weapons. Buying them in large numbers would add a different kind of equipment to a program that has already focused heavily on missiles, ammunition and spare parts.

The current buildup includes missiles with enough range to support counterstrike capabilities. In simple terms, that means the ability to strike an adversary's military targets in response to an attack, rather than relying only on weapons that intercept incoming threats.

A weaker yen is another reason the proposed budget is growing, one of the people said. When equipment is priced in a foreign currency, Japan needs more yen to pay the same foreign currency price. A larger yen allocation can therefore be partly absorbed by higher purchasing costs.

Ammunition and spare parts remain practical priorities in the existing program. Ships, aircraft and missile systems need supplies and maintenance to remain usable. The spending debate consequently involves both acquiring new weapons and keeping equipment already in service ready to operate.

Why Washington's 3.5% demand matters

United States officials have pressed Japan to spend 3.5% of gross domestic product on defense. At a meeting between Japanese and American defense officials in Washington in early October, the American side described that share as an international standard expected of allies.

Gross domestic product, or GDP, measures the value of goods and services produced in an economy. Expressing defense spending as a share of GDP allows governments to compare military budgets with the size of their economies, although the resulting amount changes as economies grow or shrink.

For Japan, spending at 3.5% would mean more than ¥20 trillion a year, according to an estimate cited in the domestic debate. Over five years, that annual level would exceed ¥100 trillion, compared with the ¥70 trillion to ¥80 trillion now being discussed. This comparison uses a constant annual amount; future GDP would affect the actual figure.

Takaichi's administration is leaning against making 3.5% an explicit target for the next five years in the revised security documents because of fiscal constraints. Another option under consideration would place it further into the future.

Officials are also considering a broader category of security spending that could include economic security and artificial intelligence. Economic security covers efforts to protect essential supplies, technologies and industries from disruption. Including such spending would widen the activities counted within a security total.

How Japan moved beyond its old spending restraint

Japan kept defense spending around 1% of the economy for many years. The shift to a 2% target in the 2022 security documents marked a major departure from that practice, with fiscal 2027 set as the target year.

The earlier restraint reflected choices about military policy and public spending. Successive governments sought to limit the burden on the economy and social programs while managing American requests for a larger Japanese defense contribution.

Several decisions explain how the present debate developed:

• 1976: Prime Minister Takeo Miki's government adopted a cabinet decision limiting defense spending to 1% of gross national product, an economic measure similar to GDP.
• About a decade later: Prime Minister Yasuhiro Nakasone's government removed the formal ceiling, although later administrations continued to give weight to the 1% benchmark.
• 2020: Japan abandoned plans to deploy the land based Aegis Ashore missile interception system.
• 2022: The government adopted the current security documents, setting approximately ¥43 trillion for fiscal 2023 through fiscal 2027 and a 2% spending target.
• April 2027: The proposed ¥70 trillion to ¥80 trillion program would begin.

Dakio Sakata, defense agency chief when the 1976 limit was established, explained its purpose as avoiding threats to other countries and protecting civilian priorities, including social welfare. Those competing demands remain part of the argument over how much Japan should spend.

Two ships put equipment choices under scrutiny

Two ships equipped with the Aegis missile defense system illustrate why the debate extends beyond the headline budget. Their estimated combined cost, from initial planning through operation, repairs and eventual disposal, is about ¥2 trillion.

Japan decided to introduce the ships after abandoning Aegis Ashore in 2020. Aegis combines radar, tracking and weapons systems to detect threats and support interception. Moving the mission onto ships creates spending requirements that continue long after construction.

The ¥2 trillion estimate covers the vessels' full service lives. It includes expenses incurred over many years, making operating and maintenance costs central to assessing the purchase.

Scrutiny of the current program has also focused on whether expensive conventional equipment will remain useful as military technology develops. That issue sits alongside the proposed drone purchases: the government must choose how to divide money among large platforms, newer technologies and the supplies needed to sustain both.

For taxpayers, the concrete issue is what the additional money buys. A spending total gives the scale of the commitment; equipment choices, delivery schedules and continuing operating bills determine the capabilities Japan receives.

Who would pay for the increase?

A corporate tax increase has emerged as a possible source of funding, drawing opposition from the business community. With annual defense spending expected to rise by amounts measured in trillions of yen, finance officials are pressing for revenue that can continue year after year.

A government advisory meeting on October 27 also raised the need for stable funding as part of the security document revisions. The fiscal argument is straightforward: personnel, maintenance and other recurring commitments require continuing payments, even after an initial equipment purchase is complete.

Corporate taxation would place part of that burden on company profits. Business resistance makes the funding decision politically difficult, while leaving the government to reconcile its military plans with other demands on public money.

At a September 27 advisory meeting, participants supported stronger defense while calling for attention to fiscal health, confidence in Japan in international markets and careful explanations to the public. Market confidence matters because governments depend on investors to buy their debt and help finance public spending.

Takaichi must turn ambition into agreement

Takaichi's defense plans require agreement within the governing camp as well as decisions on revenue and procurement. One person familiar with the discussions said the final spending figure remained subject to debate between the government and coalition partners.

Her rise to power followed a difficult political transition. In October 2025, she faced a coalition crisis after Komeito's withdrawal, which ended the Liberal Democratic Party's partnership of 26 years and complicated her route from party leader to prime minister.

The current budget negotiations put another large decision before the governing parties. Support for stronger defense must be translated into agreement on the amount, the purchases and the financial burden.

The administration has also managed how numerical targets appear in economic policy. A July cabinet decision on economic and fiscal policy placed references to NATO and other spending benchmarks in a footnote rather than setting a numerical target in the main text. A Japanese government official described the aim as lowering American expectations.

The decisions that will shape the final plan

The revision of Japan's three security documents toward the end of the year is the next major decision point. One of those documents, the Defense Buildup Program, sets out the total planned spending over five years.

The government is weighing three connected choices: how much to commit, which capabilities to buy and how to provide continuing revenue. The proposed ¥70 trillion to ¥80 trillion range gives those negotiations a scale, while the drone plans, Aegis ship costs and corporate tax debate show where the practical arguments lie.

Japan's eventual spending commitment will also have to accommodate exchange rates and equipment costs. For households and companies, the financing decision will determine how the expanded military program shares the public purse with other priorities.

Key Points

• Japan is considering ¥70 trillion to ¥80 trillion in defense spending over five years beginning in April 2027.
• The range is about 63% to 86% above the current ¥43 trillion program.
• Large drone purchases are under consideration, while a weaker yen is increasing procurement costs.
• Washington is pressing for defense spending equal to 3.5% of GDP, estimated at more than ¥20 trillion annually.
• A possible corporate tax increase has drawn business opposition as officials seek stable revenue.
• The spending total and funding choices are being debated ahead of security document revisions toward the end of the year.