Case Study: Monzo runs a regulated digital bank for 500,000+ customers with Amazon Web Services

How Monzo built a digital bank on AWS for over 500,000 customers

Monzo is a UK mobile-first bank founded in 2015 that set out to disrupt legacy banks by offering instant transfers, real‑time statements, and fee‑free spending abroad. The company needed to scale quickly, win FCA regulatory approval, and avoid monolithic legacy systems while supporting rapid customer growth to over 500,000 users and £1 billion in transactions.

To meet that challenge Monzo built a cloud-native platform on AWS, splitting its core banking into 400+ microservices running on EC2, EBS, S3, Kubernetes and Auto Scaling with a multi-account security model and CloudTrail audit logs. The result: regulatory compliance, high resilience and rapid iteration — a five‑person platform team now manages infrastructure for half a million customers, Monzo migrated to a multi‑account setup in a day, and customers get real‑time statements and faster feature delivery.

Monzo

Matt Heath

Distributed Systems Engineer