TSB Bank Data Migration Failure – A Data Testing Perspective

In this video, Sandesh Gawande, CTO of iceDQ, discusses the 2018 TSB Bank data migration failure that cost over £1 billion and affected 5.2 million customers. Drawing from official inquiries by IBM, EY, and Slaughter and May, this talk breaks down what went wrong when Sabadell Bank attempted to migrate TSB’s customer data from Lloyds’ platform to their Proteo system.

Key Topics Covered:

1. The perfect storm of failures that led to the disaster
2. Critical mistakes in data migration testing
3. Why sampling data instead of testing all data is dangerous
4. The risks of simultaneous system upgrades and data migration
5. The importance of having access to source systems and data models
6. Why automated data testing tools are essential
7. The critical role of continuous delta reconciliation

Key Takeaways:

1. Why data testing requires specialized expertise
2. The dangers of unrealistic deadlines
3. The importance of proper planning and tooling
4. Why “Big Bang” approaches are risky
5. How to avoid common data migration pitfalls
6. The critical role of data testing in major migrations
7. Risk mitigation strategies for large-scale transformations
8. Best practices for successful data migrations