Update on UTC Timing for Late 2026

INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS) Service International de la Rotation Terrestre et des Systèmes de Référence Observatoire de Paris, 61, Av.

Contact Information

• Phone: +33 1 40 51 23 35
• Email: services.iers@obspm.fr
• Web: http://hpiers.obspm.fr/eop-pc

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Date: 06 July 2026 Document: Bulletin C 72 Recipient: Entities tasked with the distribution and measurement of global time.

Official Notice: There will be an addition of a leap second no leap second introduced at the conclusion of December 2026.

Technical Time Specifications

The current temporal offset between Coordinated Universal Time (UTC) and International Atomic Time (TAI) remains unchanged.

Current Offset Equation: $\text{UTC} - \text{TAI} = -37\text{s}$

This value has been in effect since January 1, 2017, at 0h UTC and will persist until further notice.

Operational Logic

Leap seconds are integrated into UTC based on the variance of $\text{UT1} - \text{TAI}$. These adjustments are only permitted during two specific windows:

1. The end of June.
2. The end of December.

Administrative Schedule

The Bulletin C is distributed on a semi-annual basis. Its purpose is to:

• Confirm that no time step will occur at the next opportunity.
• Announce a necessary time step in UTC.

# Current System State
echo "UTC_OFFSET=-37"
echo "DEC_2026_LEAP_SECOND=FALSE"

Signed,

Christian BIZOUARD Director, Earth Orientation Center of IERS Observatoire de Paris, France