Article · Wikipedia archive · Last revised Jun 20, 2026

TONAR

Tokyo Overnight Average Rate or Japanese Yen Uncollateralized Overnight Call Rate is an unsecured interbank overnight interest rate and reference rate for Japanese yen. Mutan rate and TONA rate are the same things.

Last revised
Jun 20, 2026
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Wikipedia ↗

Tokyo Overnight Average Rate (TONA rate or TONAR) or Japanese Yen Uncollateralized Overnight Call Rate (Japanese: 無担保コールO/N物レート) is an unsecured interbank overnight interest rate and reference rate for Japanese yen.123 Mutan rate and TONA rate are the same things.

History

Japanese yen uncollateralized overnight call market started in July 1985.4

Since December 28, 2016, the Bank of Japan has recommended the TONA rate as the preferred Japanese yen risk-free reference rate.56

TONA rate is recommended as a replacement for Japanese yen LIBOR, which was phased out at the end of 2021, and Euroyen TIBOR, which will be terminated at the end of 2024.3789

Target rates

TONA rate source ↗
Bank of Japan target rates10
Dates Target rates
1998.09 - 1999.02 0.25%
1999.02 - 2000.08 Initially 0.15%, then 0%.
2000.08 - 2001.02 0.25%
2001.02 - 2001.03 0.15%
2001.03 - 2006.03 None (0%)
2006.03 - 2006.07 0.00%
2006.07 - 2007.02 0.25%
2007.02 - 2008.10 0.50%
2008.11 - 2008.12 0.30%
2008.12 - 2010.10 0.10%
2010.10 - 2013.04 0.00% - 0.10%
2013.04 - 2024.03 None (0%)
2024.03 - 0.00% - 0.10%11
2024.08 - 0.25%12

TONA Compounded Benchmarks

TONA Averages
TONA Averages are derived from the daily compounded TONA rate. The terms are 30day, 90days, and 180 days.13
TONA Index
Assets when 100 was invested in TONA on June 14, 2017.13
References

References

  1. Interest Rate Benchmark Reform (Preparedness for the Discontinuation of LIBOR) : 日本銀行 Bank of Japan
  2. "LIBOR: Where Things Now Stand | Insight | Baker McKenzie". www.bakermckenzie.com. Archived from the original on 2017-12-03.
  3. "EXPLAINER-What is SOFR? The new U.S. Libor alternative". Reuters. 3 April 2018.
  4. BOJ's Main Time-series Statistics
  5. Report on the Identification of a Japanese Yen Risk-Free Rate - Study Group on Risk-Free Reference Rates - Bank of Japan
  6. "Libor Reform – What You Need to Know". 26 September 2017.
  7. "Libor Enters 'Final Chapter' as Global Regulators Set End Dates". Bloomberg.com. 5 March 2021. Retrieved 10 March 2021.
  8. LIBOR Transition | Japanese Bankers Association
  9. JBA TIBOR Reform | JBA TIBOR
  10. 日本銀行による追加緩和の行方 ― 金融政策の現状と課題 ― 立法と調査 2019.12 No.418 参議院常任委員会調査室・特別調査室
  11. Changes in the Monetary Policy Framework - Bank of Japan
  12. Change in the Guideline for Money Market Operations and Decision on the Plan for the Reduction of the Purchase Amount of Japanese Government Bonds - Bank of Japan
  13. TONA Averages & TONA Index | QUICK
External links