Lyon’s Bold Digital Revolution: 7 Reasons the City’s Break‑Up With Microsoft Will Rock Government IT

The City of Lyon has just put Big Tech on notice. By replacing Microsoft Office with a home‑grown open‑source productivity stack and hosting all data in regional datacentres, France’s second city is betting that “digital sovereignty” can be affordable, secure and greener. This report unpacks the facts behind the announcement, brings in fresh reporting from across Europe, and gathers expert commentary on why Lyon’s move could become a blueprint for municipalities everywhere.

1. What exactly happened in Lyon?

• On 23 June 2025 the city published a communiqué entitled “La Ville de Lyon renforce sa souveraineté numérique” detailing two flagship projects:
  1. Territoire Numérique Ouvert (TNO) – a fully open‑source collaborative suite developed with the inter‑municipal digital syndicate SITIV and the Lyon Metropole.
  2. A progressive migration from Microsoft Office to OnlyOffice, Linux and PostgreSQL across all municipal workstations. lyon.fr
• TNO is hosted in regional datacentres, benefited from a €2 million grant from the National Agency for Territorial Cohesion (ANCT) and already serves “several thousand agents” in nine local authorities. lyon.frterritoirenumeriqueouvert.fr
• Local media confirm that training of civil servants began this month and that the stated goal is to “escape American software dependency.” bfmtv.comlyonmag.com

Key quote

“We are proud to place Lyon on a trajectory of digital sovereignty … to protect citizens’ data and stimulate the local economy.”
— Bertrand Maes, Deputy Mayor for Digital Policy lyonmag.com

2. Why France (and Europe) care about “digital sovereignty”

• French diplomat Henri Verdier argues that sovereignty “is not about protectionism … it’s about the ability to make autonomous democratic choices online.” cepa.org
• The European Commission’s 2025 State of the Digital Decade report warns that Europe still “has not harnessed the full power of open source … essential for tech autonomy.” data.consilium.europa.eu
• Last week’s NGI Forum 2025 opened with the slogan “Building an Open Internet Stack for European Digital Sovereignty.” digital-strategy.ec.europa.eu

3. Inside “Territoire Numérique Ouvert”

• The Zimbra integration alone is cutting maintenance costs “by at least 50 %”, notes SITIV director Stéphane Vangheluwe. sitiv.fr
• Over 50 % of public contracts for TNO went to Rhône‑Alpes SMEs, 100 % to French companies, aligning spend with local economic policy. lyon.fr

4. Follow the money: licences, jobs and clouds

• Licence savings – Industry analysts at InformatiqueNews estimate that Lyon and nearby Ville‑la‑Grand will avoid “several million euros annually” in Microsoft subscription costs. informatiquenews.fr
• Cloud capacity – French provider OVHcloud attributes a 17 % public‑cloud revenue jump this quarter to demand for sovereign solutions. reuters.com
• Data‑centre boom – Research & Markets counts 1 GW of new French white‑floor space in the pipeline, driven largely by local‑sovereignty requirements. globenewswire.com

5. Security, compliance and antitrust tail‑winds

• French search engine Qwant has asked the national antitrust authority for interim measures against Microsoft, citing unfair bundling that hurts domestic providers. reuters.com
• Microsoft is simultaneously sweetening its “sovereign cloud” offer to calm EU regulators. subscriber.politicopro.com
• Even so, the company still faces a separate probe over Office‑Teams tying. reuters.com
• These headwinds make municipal exits like Lyon’s politically easier.

6. A greener digital footprint

Lyon argues that extending PC lifecycles by switching to Linux avoids premature hardware refreshes—the manufacturing phase accounts for the majority of a device’s emissions, a point echoed by open‑source advocacy group FSFE in its April symposium. fsfe.org

7. The domino effect across Europe

PC Gamer’s headline sums it up: “Governments dump Windows for digital sovereignty, not just to save money.” pcgamer.com

8. Voices from the field

• Bertrand Maes (City of Lyon): “Protecting citizens’ data also protects democracy.” lyonmag.com
• Stéphane Vangheluwe (SITIV): “Mutualising open‑source tools is about sobriety, efficiency and sovereignty.” sitiv.fr
• Amb. Henri Verdier (French Special Envoy for Digital): “Digital sovereignty is not anti‑American; it’s the freedom to implement the rules our people decide.” cepa.org

9. Risks and hurdles

1. User retraining – comments from LyonMag readers highlight legacy macros and email deliverability as pain‑points. lyonmag.com
2. Vendor lock‑out retaliation – Microsoft’s cloud concessions show big providers will fight to keep market share. subscriber.politicopro.com
3. Interoperability – EU’s Digital Decade report flags that Europe “is not yet harnessing the full power of open source,” signalling ongoing gaps. data.consilium.europa.eu

10. What happens next?

• Summer 2025 – City departments migrate first 2,000 desktops to OnlyOffice & Linux.
• Q4 2025 – Lyon presents results at the Gaia‑X Summit on federated data infrastructure. gaia-x.eu
• 2026 budget cycle – Expected scaling to schools and cultural institutions if pilot KPIs (cost, uptime, user satisfaction) are met, monitored by DINUM’s open‑source observatory. numerique.gouv.fr

Bottom line

Lyon’s switch is more than a symbolic jab at U.S. tech giants. It bundles economic stimulus for local SMEs, climate‑aligned hardware policy, and compliance with shifting EU rules into one coherent strategy. If the city delivers on usability and support, TNO could become the reference architecture for digitally sovereign public services across Europe.