Challenge

BT faced one of the most complex data migration challenges in the UK telecoms sector: decommissioning more than 20 legacy platforms and migrating 27 petabytes of critical data to Google Cloud Platform, all without disrupting the data-driven operations the business depends on. The scale alone was formidable, but the deeper risk lay in doing it without a coherent strategy. A poorly governed migration of this magnitude could expose BT to significant cost overruns, data integrity failures, and security vulnerabilities, derailing the very ambitions the programme was designed to unlock. BT needed a partner with both the strategic authority to define the path and the technical depth to execute it.

Solution

We took on the role of strategic partner for the programme, providing expert guidance on cloud adoption best practices while architecting the migration approach and building the accelerators needed to move at pace. The team executed the migration of all 27 petabytes of data using Dataflow for pipeline orchestration, Cloud Storage for scalable and secure data landing, and BigQuery as the analytical foundation for BT's future data estate. Alongside the technical delivery, we developed a comprehensive five-year roadmap and fully costed plan, giving BT's leadership a clear, structured path toward realising new data products, services, and commercial opportunities on Google Cloud.

Outcomes

With the migration complete and a trusted data fabric established, BT is now positioned to decommission its legacy platform estate and redirect the associated costs toward innovation rather than maintenance. Data governance and security controls are embedded throughout the new environment, ensuring that data movement across the estate is auditable, compliant, and reliable. The five-year strategic roadmap gives BT the clarity and confidence to scale its data capabilities systematically, accelerating time-to-value and laying the groundwork for a genuinely data-led business.