COSC Releases Excellence Chronometer: A Stricter Standard in Swiss Chronometry

COSC Raises the Bar with New Excellence Chronometer Certification

In February 2026, the Contrôle Officiel Suisse des Chronomètres (COSC) officially unveiled the Excellence Chronometer, a new and more demanding certification standard that represents the most significant update to Swiss chronometry testing in decades. The announcement marks a pivotal moment for an industry where precision has always been the ultimate benchmark.

What Is the Excellence Chronometer?

The traditional COSC chronometer certification requires mechanical movements to maintain accuracy within -4/+6 seconds per day across multiple positions and temperatures. The new Excellence Chronometer standard introduces significantly tighter tolerances, requiring movements to achieve accuracy within -2/+4 seconds per day — essentially doubling the precision demands placed on manufacturers.

Why This Matters for the Watch Industry

The Excellence Chronometer responds to a growing demand from both brands and consumers for greater accountability in timekeeping precision. While COSC has certified approximately 1.8 million movements annually in recent years, the new standard is expected to initially apply to a smaller subset of premium calibers from brands willing to invest in tighter manufacturing tolerances.

According to COSC leadership, the initiative was driven by the need to adapt to evolving technology and consumer expectations. With brands like Omega, Rolex, and Tudor already offering internal certifications that exceed COSC standards, the official Swiss testing body needed to remain relevant as the benchmark for precision.

Impact on Brands and Consumers

• Manufacturers will need to invest in tighter quality control and potentially more refined components to meet the new standard
• Consumers gain a clearer differentiator between standard and premium-grade movements
• The pre-owned market may see Excellence Chronometer-certified watches command premiums over standard COSC pieces

Which Brands Are Expected to Adopt It?

While COSC has not yet released a full list of participating brands, industry analysts expect companies like Tissot, Certina, Mido, and Formex — brands that already emphasize COSC certification as a selling point — to be among the first to offer Excellence Chronometer-rated movements.

Frequently Asked Questions

Is Excellence Chronometer replacing the standard COSC certification?

No. The Excellence Chronometer is an additional tier alongside the existing COSC chronometer standard. Both certifications will continue to exist, offering brands flexibility in how they position their movements.

Will Excellence Chronometer watches cost significantly more?

Expect a moderate price premium. The tighter tolerances require more rigorous testing and quality control, which may add $200–$500 to the retail price depending on the brand and movement.

How does this compare to Rolex's Superlative Chronometer?

Rolex's internal Superlative Chronometer standard (-2/+2 seconds/day) remains stricter than the new Excellence Chronometer (-2/+4 seconds/day). However, the COSC standard is independently verified, whereas Rolex's certification is performed in-house.

Sources: Monochrome Watches, COSC Official Communications, aBlogtoWatch

For more on watch certifications, visit our complete guide to COSC certification and explore our guide to watch accuracy.