Chapter 2 2.4

Budget Deficits and Debt Servicing

Understanding Japan's budget deficit and the growing burden of debt servicing costs

The Budget Deficit Reality

FY2025 General Account Budget: ¥115.5 trillion (record high)

Revenue vs. Spending

Total Revenue: ¥115.5 trillion

  • Tax revenue: ¥78.4 trillion (67.9%)
  • Bond issuance (new money): ¥28.6 trillion (24.8%)
  • Other revenue: ¥8.5 trillion (7.3%)

Key point: Despite record tax revenues, Japan must still borrow ¥28.6 trillion annually to fund current operations. This is nearly 25% of the budget funded by debt—a persistent structural deficit.

Where the Money Goes (FY2025)

Category Amount % of Budget
Social Security ¥38.3T 33%
Debt Servicing ¥28.2T 24%
Local Government Transfers ¥16.7T 14%
Defense ¥8.7T 8%
Public Works ¥6.3T 5%
Education & Science ¥5.5T 5%
Other ¥11.8T 10%

Critical observations:

  • Debt servicing (¥28.2T) is the second-largest budget item after social security, consuming 24% of total spending
  • Defense spending rose 9.7% to ¥8.7T, reflecting Japan’s security policy shift
  • Social security and debt servicing together account for 57% of all government spending

Debt Servicing Costs: The Hidden Burden

FY2025 Debt Servicing: ¥28.2 trillion (record high, up from ¥27.0T in FY2024)

This massive expense breaks down into:

1. Interest Payments: Estimated ¥11-12 trillion

  • Coupon payments on all outstanding JGBs
  • Paid to bondholders (domestic banks, insurers, BOJ, foreign investors)
  • Average interest rate: Rising from ~0.9% as BOJ normalizes policy
  • FY2025 assumption: MOF budget assumes 10-year JGB yield rises to 2.0% (first time in 13 years)

Why are costs rising?

  • BOJ policy normalization: ended YCC (March 2024), raised policy rate to 0.5%
  • Higher issuance costs: new bonds issued at higher yields
  • Refunding at higher rates: maturing low-yield bonds replaced with higher-yield bonds
  • Persistent inflation: BOJ targeting 2% inflation sustainably

The risk: If rates normalize to 3%, interest costs could reach ¥35-40T annually, consuming half of all tax revenue

2. Debt Redemption Fund: Estimated ¥16-17 trillion

  • Mandatory contribution to gradually reduce debt
  • Required by the Special Fiscal Law
  • In practice, this money is used to buy back JGBs before maturity or pay down debt

Interest Coverage Ratio

A critical fiscal health metric:

\[\begin{align} \text{Interest Coverage Ratio} &= \frac{\text{Tax Revenue}}{\text{Interest Payments}} \\ &= \frac{¥78.4T}{¥11-12T} \\ &= 6.5-7.1x \end{align}\]

Interpretation:

  • >10x: Healthy (interest easily covered)
  • 5-10x: Manageable (Japan’s current state)
  • <5x: Stress (significant fiscal constraint)
  • <3x: Crisis (risk of debt spiral)

Historical comparison:

  • 1990: 18.5x (¥60.1T revenue / ¥3.25T interest) ← Peak
  • 2009: 4.5x (¥38.7T revenue / ¥8.6T interest) ← Crisis level
  • 2025: 6.5-7.1x (¥78.4T revenue / ¥11-12T interest) ← Improving but fragile

Key concern: Despite record tax revenues, the ratio is only slightly better than a decade ago because interest costs are rising. The improvement is fragile—dependent on continued economic growth and controlled rate increases.