Chapter 4 4.4

Issuance Schedules and Calendars

MOF auction calendars, issuance patterns across maturities, and market preparation

The Rhythm of the Market: MOF Issuance Plans

The JGB primary market runs on a highly predictable, transparent, and regular schedule set by the Ministry of Finance (MOF). This transparency is crucial for market stability, allowing investors to plan their cash needs and investment strategies months in advance.

The issuance process is governed by two key documents available on the MOF's official website:

📄 Official MOF Resources:

The issuance process is governed by two key documents: the Annual Plan and the Monthly Calendar.

1. The Annual JGB Issuance Plan

Published every December for the upcoming fiscal year (which starts April 1st), this is the government's high-level borrowing strategy. It outlines:

  • Total Issuance Amount: The total amount the MOF plans to borrow, broken down by new financing (deficit) and refinancing (rolling over old debt).
  • Issuance by Maturity: The planned total (or range) to be issued for each tenor (e.g., ¥32.4 trillion in 10-year bonds).
  • Issuance Frequency: How often each bond will be auctioned (e.g., "monthly").
  • Strategic Goals: Any strategic shifts, such as increasing 40-year issuance to lengthen the average maturity of government debt.

This document is the market's bible for the year. It allows large investors like pension funds to forecast the supply of bonds they need to buy.

2. The Monthly Auction Calendar

On the last business day of each month, the MOF releases the detailed auction calendar for the *following* month. This document provides the specific, hard dates that traders program into their systems.

It includes:

  • Auction Dates: The exact day (e.g., Oct 7, 2025) for each auction.
  • Issuance Amount: The precise amount to be sold (e.g., ¥2.7 trillion).
  • Issue Date & Maturity Date: The T+1 settlement date and the exact maturity date of the new bond.

Typical JGB Auction Frequency

While the exact schedule changes, the MOF follows a very regular "rhythm" of issuance. This ensures a consistent supply across the entire yield curve.

JGB Tenor (Maturity) Typical Auction Frequency Timing
T-Bills (3-mo, 6-mo) Weekly Typically held every Monday and Tuesday.
2-year, 5-year, 10-year Monthly These benchmark bonds are issued every single month to ensure high liquidity. The 10-year is the most closely watched.
20-year, 30-year Monthly Also issued monthly to meet the strong, steady demand from life insurers and pension funds (ALM buyers).
40-year Bi-Monthly (Every 2 months) Issued less frequently as it's a more specialized product.
Inflation-Indexed (JGBi) Quarterly (Every 3 months) This is a small, niche market, so issuance is infrequent.

New Issues vs. Reopenings: The Core of JGB Liquidity

One of the most critical—and often misunderstood—aspects of JGB issuance is the distinction between new issues and reopenings (re-issuances). This mechanism is fundamental to maintaining deep, liquid benchmark bonds across the yield curve.

New Issues vs. Reopenings

New Issue

Definition:

A brand new bond with a unique ISIN code, newly set coupon rate, and fresh maturity date.

Coupon Setting:

The MOF sets the coupon just before the auction to match current market yields (typically rounded to nearest 0.1%). This ensures the bond trades near par (¥100).

Frequency (10Y Example):

New 10-year benchmark created quarterly (March, June, September, December)

Typical Auction Size:

¥800 billion - ¥1.2 trillion

Purpose:

  • Creates new "on-the-run" benchmark
  • Resets coupon to current market rates
  • Establishes fresh price discovery point
Reopening (Re-issuance)

Definition:

Additional auction of an existing bond—same ISIN, same coupon, same maturity. Increases outstanding amount of that specific bond.

Coupon:

Unchanged—uses the original coupon set at new issuance. This means reopenings often trade at premium/discount to par.

Frequency (10Y Example):

Typically reopened 2-3 times in the months following new issue

Typical Auction Size:

¥800 billion - ¥1.2 trillion (same as new issue)

Purpose:

  • Builds outstanding to ¥3-5 trillion
  • Creates deep, liquid benchmark issue
  • Maintains orderly supply without fragmenting market

Why Reopenings Matter: The Liquidity Imperative

Reopenings are not just a convenience—they are essential to maintaining a healthy, functional JGB market. Here's why:

Benefit Explanation
Concentrated Liquidity By reopening the same bond 2-3 times, the MOF creates a single, large issue with ¥3-5 trillion outstanding. This concentrated size makes it easier to buy/sell large blocks without moving the market.
Benchmark Formation Large, liquid bonds become natural "benchmarks" for pricing corporate bonds, swaps, and other fixed-income instruments. Without reopenings, the market would fragment across dozens of small, illiquid issues.
Futures CTD Stability Futures contracts track the CTD bond (Section 2.6). A large, liquid reopened bond is more likely to become and remain the CTD, reducing basis risk for hedgers.
Reduced Issuance Costs Auctions of liquid bonds attract more bidders and tighter bid-to-cover ratios, lowering the government's borrowing costs through better pricing.
International Comparability US Treasuries, German Bunds, and UK Gilts all use reopenings extensively. Japan's approach aligns with global best practices, making JGBs accessible to international investors familiar with this structure.

Worked Example: Lifecycle of a 10-Year JGB Benchmark

Example: JGB #385 (Hypothetical Issue)

March 2025 - New Issue

  • MOF creates JGB #385, 10-year maturity (Mar 20, 2035)
  • Coupon set at 1.0% (matching current 10Y yield)
  • ISIN: JP1103851ABC (unique identifier)
  • Auction: ¥1.0 trillion issued
  • Total Outstanding: ¥1.0 trillion

April 2025 - First Reopening

  • MOF reopens same JGB #385
  • Coupon: 1.0% (unchanged)
  • ISIN: JP1103851ABC (same as March)
  • Auction: ¥1.2 trillion additional
  • Total Outstanding: ¥2.2 trillion

May 2025 - Second Reopening

  • MOF reopens same JGB #385 again
  • Auction: ¥1.3 trillion additional
  • Total Outstanding: ¥3.5 trillion

June 2025 - New Benchmark Created

  • MOF issues JGB #386 (new benchmark)
  • JGB #385 becomes "off-the-run" (no longer the current benchmark)
  • JGB #385 remains highly liquid with ¥3.5T outstanding and continues trading actively

💡 Key Insight: The ¥3.5 trillion outstanding in JGB #385 makes it one of the most liquid fixed-income instruments in Asia. This would be impossible if the MOF issued a new bond every month instead of reopening.


Liquidity Supply Auctions (流動性供給入札)

In addition to regular calendar auctions, the MOF conducts Liquidity Supply Auctions (ryūdōsei kyōkyū nyūsatsu / 流動性供給入札) to maintain market functioning during periods of stress or to enhance liquidity in specific off-the-run issues.

What Are Liquidity Supply Auctions?

These are ad hoc, unscheduled auctions where the MOF sells additional amounts of existing (usually off-the-run) bonds to address temporary market illiquidity or seasonal demand spikes.

Feature Description
Announcement Typically announced 1-2 weeks before auction (unlike regular calendar auctions scheduled months ahead)
Target Bonds Usually off-the-run benchmarks or bonds with temporary scarcity in the repo market
Auction Size Smaller than regular auctions (¥200-500 billion typical)
Purpose Alleviate repo fails, smooth yield curve discontinuities, or meet unexpected institutional demand
Frequency Irregular—used only when needed (0-10 times per year)

Historical Use Cases

  • March 2020 (COVID-19 Crisis): MOF conducted liquidity supply auctions for 10Y and 20Y JGBs as the pandemic caused market dysfunction and liquidity hoarding by foreign investors.
  • Fiscal Year-End (March): Seasonal liquidity auctions to meet Japanese banks' balance sheet needs before fiscal year-end reporting.
  • BOJ Policy Changes: When the BOJ adjusts YCC targets or conducts large operations, the MOF may supply additional bonds to smooth market adjustment.
📘 Market Impact: Liquidity supply auctions are generally viewed positively by dealers, as they reduce repo fails and special rates. However, they can also signal market stress, so traders watch these announcements carefully for insights into BOJ/MOF market concerns.

References

  1. Japan Ministry of Finance. "JGB Issuance Plan & Calendar." Available at: https://www.mof.go.jp/english/policy/jgbs/debt_management/plan/index.htm.
  2. Japan Ministry of Finance. "Auction Calendar." Available at: https://www.mof.go.jp/english/policy/jgbs/auction/calendar/index.htm.