# The Leap Second Is Officially Retired by 2027 Global standards bodies will stop adjusting Coordinated Universal Time to prevent critical system failures. - **Source:** [Wired](https://www.wired.com) - **Published:** 2026-10-16 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/202f2425-783a-4905-93dc-0bc453427147 ## The End of Leap Seconds The International Bureau of Weights and Measurements officially announced the discontinuation of leap seconds starting in May 2027. Since 1972, thirty-two leap seconds have been added to Coordinated Universal Time to bridge the gap between atomic clocks and Earth's rotation. This decision concludes three decades of intense debate within the global metrological community. ## Atomic vs Astronomical Time Leap seconds were implemented because Earth's rotation is slowing down due to tidal friction, atmospheric changes, and molten core movements. Atomic clocks provide precise time, but they drift from astronomical time, known as UT1. The leap second acted as a corrective measure, ensuring these two distinct timekeeping methods remained synchronized for global digital operations. ## Technical Risks and Failures While intended for precision, leap seconds created significant instability for databases and APIs relying on UTC. Companies like Google and Meta utilized smearing methods to mitigate errors, but others faced severe outages. In 2012, Qantas experienced a major booking system failure directly linked to the insertion of a leap second into their digital infrastructure. ## The Negative Leap Second Threat Recent climate change impacts have accelerated Earth's rotational speed, raising the unprecedented risk of requiring a negative leap second. Experts feared that a negative adjustment would cause catastrophic failures, as systems were never designed to subtract a second. This potential for instability accelerated the decision to abandon the practice entirely by 2027. ## Urgency from Industry Testing Patrizia Tavella, director of the BIPM time department, confirmed that industry standards groups identified multiple system failures during tests involving negative leap seconds. These findings solidified the consensus that the risks outweighed the benefits of maintaining perfect alignment. Consequently, the organization set the 2027 deadline to ensure global systems remain stable and predictable. ## Symbolic Timing for Change The implementation date of May 20, 2027, was chosen to coincide with the anniversary of the 1875 Metre Convention and World Metrology Day. This symbolic date marks the transition away from manual time adjustments. By choosing this moment, the BIPM highlights the evolution of global timekeeping standards in an increasingly digitized, interconnected world. ## Future Timekeeping Implications Moving forward, UTC will simply accumulate seconds without further manual intervention. While atomic and astronomical time will eventually drift apart, the divergence will be negligible for current technological needs. Systems relying on UTC will no longer require complex logic to handle time jumps, significantly simplifying backend architecture and reducing maintenance overhead for global developers. ## Long-term Temporal Management The BIPM has discussed the concept of a leap hour to address long-term drift, but this remains a concern for the distant future. Because there are 3,600 seconds in an hour, such an adjustment is millennia away. For now, the focus remains on ensuring that current digital systems operate without the threat of unexpected temporal interruptions. ## Sources covering this story - https://www.wired.com/story/leap-second-is-abolished-bipm-says/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._