How Millennium bcp Uses BigQuery ML to Boost Loan Conversion Rates

Millennium bcp, Portugal's largest private bank by business volume, had long relied on physical branch visits for personal loan applications — a model that constrained scalability and failed to meet the expectations of increasingly digital-first customers. Clients were required to visit in person during limited hours and endure slow, manual processes. By 2023, the bank set an ambitious goal: meaningfully grow digital sales of personal loans while ensuring outreach was limited to existing customers, the only segment eligible to complete the digital loan journey.

To address this challenge, Millennium bcp's in-house digital marketing team — spanning media, copywriting, design, and analytics — turned to Google Cloud, a platform the bank had already been building on for over six years. The team leveraged BigQuery's machine learning capabilities to analyze the behavioral patterns of existing clients who had previously taken out personal loans. These insights powered predictive models that identified other customers with a high likelihood of doing the same, segmenting the broader customer base into three tiers of interest: low, medium, and high.

With these audience models in place, the team integrated the outputs into Google Analytics 4 to dynamically generate tailored audience segments. These segments were then activated across multiple channels — Firebase for personalized in-app messaging and Display & Video 360 for precision-targeted paid media campaigns. Critically, the entire solution was built on first-party data, ensuring full compliance with evolving privacy regulations while maintaining a high degree of personalization and relevance.

The results significantly exceeded expectations. In owned media, BigQuery-powered audiences delivered a 2.6x higher conversion rate and 2.4x greater conversion volume compared to other first-party audiences. In paid media, conversion volume doubled, conversion rates were 1.9x higher, and cost per acquisition fell by 36%. The project demonstrated that a fully in-house team, armed with the right data infrastructure, could execute a sophisticated, end-to-end digital transformation.

Today, Millennium bcp stands as a benchmark in data-driven digital banking. The bank continues to deepen its use of Google Cloud tools, with a stated commitment to remaining an early adopter of new capabilities. The success of this initiative has accelerated a broader cultural shift — from a traditional, branch-centric mindset to a fully digital, analytics-led approach to customer engagement.