It had long been criticized for not having changed since 1976 and for focusing solely on the movement. Now, the Official Swiss Chronometer Testing Institute (COSC) is preparing to evolve the standard of Swiss watchmaking excellence. As the historic guardian of chronometer certification under ISO 3159, the COSC—a non-profit organization recognized as serving the public interest—is announcing a long-awaited transformation: the Super-COSC (still an unofficial name). Its rollout is planned for mid-2026, with a full presentation expected by the end of 2025.
The goal? To enhance end-customer reassurance with tests that remain neutral and independent—but are now conducted on the complete watch head, under conditions closer to real-life wear. Among the new features is a precision check in dynamic positions, better reflecting how watches are actually worn. An interview with CEO Andreas Wyss follows.
A New Level of Excellence
Will the Super-COSC replace the ISO 3159 standard, in place since 1976, or build on it? “It will be a set of additional tests,” explains Andreas Wyss. “The ISO 3159 standard remains the foundation. To earn the Super-COSC certification, a movement must first pass the classic chronometric tests. Then, the entire watch will undergo a series of tests reflecting real-world usage.”
Stepping into the Life of a Watch
The real innovation? A testing protocol that simulates the daily wear of a watch. Gone are measurements in fixed positions—enter dynamic or semi-dynamic cycles. “We must stay reasonable, since we’ll be testing large volumes of watches [the COSC certified 2,376,987 pieces in 2024], while ensuring their safety,” Wyss notes. The tests will simulate the movements of an average wearer—someone who works, sleeps, takes off their watch on weekends… In short, a watch that lives a normal life, but without extremes. “This approach won’t go as far as reproducing Rafa Nadal’s arm movements during a four-hour match at Roland-Garros.” Extreme shocks or accidents won’t be included either. “We’re not guaranteeing the impossible—but the reasonable. A watch owner must understand that if their watch suffers an accident, it may be affected.”
Power Reserve, Magnetism, and More
The Super-COSC will also test power reserve, verifying that a watch truly delivers the claimed autonomy. Magnetic resistance is also expected to be included, with realistic thresholds. While METAS’s Master Chronometer standard or Rolex’s Superlative Chronometer aim for extreme benchmarks—like 15,000 Gauss resistance (equivalent to an MRI, which most people never encounter)—Super-COSC targets everyday protection. “We’re aiming for enough resistance to handle daily exposure—phones, magnetic purse clasps, laptops…”
Achieving higher levels of magnetism resistance often requires patented technologies or highly specialized materials. “We want to avoid elitism and offer a higher-level challenge that’s ambitious yet achievable, reflecting the genuine efforts of Swiss watchmakers.”
Water Resistance, the Big Question
A sensitive topic. “The current method of certifying water resistance is difficult to industrialize reliably,” admits the CEO. “If water gets into a watch, immediate intervention is needed—something brands can do internally, but not the COSC. As a neutral organization, we never handle the watch. A water resistance test would require either a brand’s watchmaker to be present on-site, or a highly regulated protocol—which we haven’t yet finalized.” More details to come at the end of 2025, when the exact terms of this Super-COSC will be revealed.
Swiss and Neutral, the Winning Combo!
The COSC also emphasizes its neutrality and experience in handling high volumes in a traceable and rigorous way. “Even though Rolex’s Superlative Chronometer tests are carried out to the highest standards, they are done internally—not by a neutral and independent body like the COSC. As for METAS, they do an excellent job, but let’s not forget that we rely on 50 years of experience.”
A Certification Also Deployed… Within Brands
The COSC plans two operating models for the Super-COSC. The classic model, in its own laboratories, for brands without dedicated infrastructure. And a decentralized model, carried out within the brands themselves, with periodic audits and equipment connected to the COSC’s systems to ensure data integrity—with the data retained for ten years. “Brands prefer not to ship their watch heads, since that always involves certain risks. A decentralized lab is a suitable solution,” notes Andreas Wyss.
New President, New Momentum
Finally, this strategic shift at COSC coincides with the arrival of a new president, Sébastien Cretegny, unanimously elected in May 2025. Aged 45, an entrepreneur in the field of sustainability and a former watch industry professional, he represents a new generation. One of his missions: to promote COSC as a demanding and visible partner in service of Swiss brands.
The Super-COSC doesn’t aim to reinvent watchmaking, but to restore meaning to the promise of “Swiss Excellence Certified.” A promise of a reliable, high-performance watch, independently tested. A promise to understand, to feel… and to wear.
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