The UK's cloud computing sector is at a pivotal moment as the Competition and Markets Authority (CMA) intensifies its scrutiny of dominant players Amazon Web Services (AWS) and Microsoft. This investigation has profound implications for competition, innovation, and the broader digital economy in the UK.

The CMA's Investigation: Unveiling Market Dynamics

In October 2023, the CMA launched an in-depth investigation into the UK's cloud services market, following concerns raised by Ofcom about potential anti-competitive practices. The CMA's provisional findings, published in January 2025, revealed that AWS and Microsoft collectively hold a significant share of the market, each commanding between 30% to 40% of UK customer spending on cloud services. Google, the next largest provider, holds a much smaller share.

The investigation highlighted several key issues:

  • Limited Provider Choice: Customers face a restricted selection of cloud service providers, leading to reduced competition.

  • Barriers to Switching: Technical and commercial obstacles make it challenging for customers to switch between providers or adopt multi-cloud strategies, potentially locking them into less favorable terms.

  • Licensing Practices: Microsoft's software licensing terms were found to disadvantage competitors like AWS and Google, further entrenching its market position.

Industry Reactions: Divergent Perspectives

The CMA's findings elicited varied responses from industry stakeholders.

Microsoft criticized the CMA's report, stating it "misses the mark again, ignoring that the cloud market has never been so dynamic and competitive, with record investment, and rapid, AI-driven changes." The company argued that the recommendations failed to account for Google's growing presence in the market.

Amazon also disputed the CMA's conclusions, asserting that the proposed actions were "unwarranted and undermine the substantial investment and innovation that have already benefited hundreds of thousands of UK businesses." The company warned that such interventions could make the UK a global outlier, potentially deterring investment.

In contrast, Google welcomed the CMA's findings, describing them as a "watershed moment." The company emphasized the need for swift action to ensure fair pricing and to foster choice, innovation, and economic growth in the UK.

Potential Regulatory Actions: Strategic Market Status

The CMA is considering designating AWS and Microsoft with Strategic Market Status (SMS) under the Digital Markets, Competition and Consumers Act 2024. This designation would grant the CMA enhanced powers to impose conduct requirements and pro-competition interventions. However, the CMA has indicated that any SMS investigations will not commence until early next year.

Broader Implications: Data Sovereignty and Market Concentration

The investigation also brings to light concerns about data sovereignty. Microsoft has acknowledged that under the U.S. Cloud Act, it cannot guarantee full data sovereignty for European Union customers, as the U.S. government can demand data from U.S.-based companies, even if stored in the EU. This raises significant privacy and national security concerns for UK businesses relying on U.S. cloud providers.

Furthermore, the dominance of U.S. companies in the European cloud market is evident. Amazon, Microsoft, and Google collectively hold 70% of the European cloud market, while European providers have seen their share decline from 29% in 2017 to 15% in 2025. This concentration raises questions about the competitiveness and resilience of the market.

Conclusion: Navigating the Future of the UK Cloud Market

The CMA's investigation underscores the need for a balanced approach to regulation that fosters competition and innovation while ensuring fair market practices. As the UK cloud market continues to evolve, stakeholders must navigate these complex dynamics to promote a vibrant and competitive digital economy.

The outcomes of this investigation could set a precedent for how cloud services are regulated globally, influencing policies on market competition, data sovereignty, and technological innovation.