No leap second at the end of December 2026
The IERS announcement confirms a normal end to December's UTC minute. This is separate from daylight saving and leap years.
What the announcement says
IERS Bulletin C 72, dated 6 July 2026, states that no leap second will be introduced at the end of December 2026. The US Naval Observatory also publishes this outcome in its leap-second announcement. This October briefing points readers to that earlier decision; it is not a new decision made this month. The announcement concerns the end of December 2026 and should not be read as a guarantee about every future year or as the abolition of leap seconds.
This is not a local clock change
A leap second concerns the UTC time scale, not a one-hour seasonal shift in a city's civil time. It is also different from the extra day in a leap year. There is no instruction here to move a household clock forward or backward by an hour. The UTC and local time guide explains how regional offsets turn a shared instant into local times. A New Year's event in Paris still needs its ordinary local date, time and regional zone.
What to do with event times and timestamps
For everyday invitations, publish the event time normally and let updated systems handle their timekeeping. Do not add or subtract an atomic-time offset from a calendar entry yourself. If you are interpreting software data, check which time scale and timestamp convention the system uses; a number without that context can be misleading. Our Unix timestamp guide and timestamp converter cover ordinary timestamp interpretation. The December announcement does not certify the clock accuracy or synchronization of an individual device.
Sources
Related reading
Unix timestamps: seconds, milliseconds and local displays
Understand what the number represents before using it in an export, log or integration.
UTC and local time: a practical explanation
Learn what an offset tells you, what it leaves out and how to write an unambiguous time.