Case Study: ASOS achieves a scalable, high-performance global shopping experience for 15.4 million customers with Microsoft Azure

Top online retailer bets on Azure to provide a stellar experience for 15.4 million customers worldwide

ASOS, a leading UK online fashion retailer with 15.4 million customers, needed to replace its aging monolithic on‑premises e‑commerce platform to support rapid global growth, a mobile‑first audience, and highly personalized shopping experiences. The company required a flexible, scalable platform that could handle multiple languages, payment and delivery options, eliminate single points of failure, and speed up feature delivery.

ASOS rebuilt its platform as cloud‑based microservices on Microsoft Azure—using Azure Cosmos DB, Azure SQL Database, Azure Traffic Manager and PaaS tooling—enabling CI/CD, regional deployments, and front‑end personalization. The migration accelerated development (1,300 releases in a quarter), delivered automated multi‑region resiliency and high scale—serving 167 million Black Friday requests, peaking at 3,500 product API req/s (48 ms avg), and reaching 22 orders/s on Black Friday and 33 orders/s on Cyber Monday (vs. 9 orders/s the prior year).

ASOS

Bob Strudwick

Chief Technology Officer