A nationwide network modernisation led by CETIN International and CETIN Networks Slovakia has reshaped the mobile landscape in Slovakia — delivering one of the most advanced, high-capacity mobile infrastructures in Central Europe.

The Challenge

O2 Slovakia set out to bring its customers a premium mobile experience built on outstanding coverage, high-speed data, and superior reliability. To achieve this, it needed a full-scale network transformation — replacing outdated technologies, expanding capacity, and preparing for the next generation of 5G services.

The CETIN Solution

As the infrastructure partner behind the scenes, CETIN International, through its local entity CETIN Networks Slovakia, delivered a comprehensive modernisation program across the entire country — from Bratislava and Košice to 70 districts nationwide.

Over the course of 22 months, CETIN executed one of the largest telecom infrastructure projects in Slovak history:

• Replaced all legacy radio technologies with next-generation Ericsson equipment
• Built hundreds of new base stations, resulting in 50% more transmitters in the O2 network
• Integrated high-capacity midband (1800–2100 MHz) and C-band (3400–3800 MHz) layers
• Expanded optical transport backhaul, boosting network capacity and resilience
• Decommissioned 3G services, reallocating spectrum to enhance 4G and 5G
• Laid the foundation for 5G Standalone (SA) and future 700 MHz deployments

“The modernisation project began three years ago in Bratislava and Košice. Since then, we’ve expanded district by district, adding hundreds of new sites and transforming O2’s infrastructure into a robust, future-ready network,” said Juraj Kodýdek, CEO of CETIN Networks Slovakia.

The Results

The transformation has had a measurable impact on network performance, user experience, and national digital readiness:

• 97.47% of the Slovak population now covered by O2’s 5G network
• 74% of all mobile data traffic already runs over 5G
• 45% improvement in call stability
• Higher customer satisfaction confirmed by independent surveys

O2 has invested more than €100 million in this network renewal — and thanks to infrastructure sharing with CETIN, modernisation goals were achieved faster, with improved quality and lower environmental impact.

The Impact

The upgraded network now provides industry-leading consistency and performance, meeting the needs of even the most demanding users. O2 continues to expand coverage, with the goal of reaching over 99% of the population by the end of the year.

As Slavomír Pšenák, CTO of O2 Slovakia, noted:

“Our modernised network now carries more than 74% of customer data over 5G. With coverage exceeding 97%, nearly everyone in Slovakia can experience the benefits of our next-generation network — and we’re continuing to optimise and enhance its quality.”

The Road Ahead

This project marks a milestone for Slovakia’s digital infrastructure — but it’s just the beginning. With 5G SA expansion on the horizon, CETIN International remains committed to strengthening Slovakia’s connectivity backbone, supporting innovation, and enabling the country’s digital future.