A strategic partnership: from new digital banking to payments modernisation with Mambu
Western Union’s successful launch of its digital banking app in 2022 marked a major step in the broader partnership with Mambu. Building on that foundation, the collaboration has continued by fully modernising its European payment operations in just 6 months — processing all SWIFT, SEPA and T2 payments with unprecedented agility.
- live markets for digital banking app: Germany, Italy, Romania and Poland
- months from legacy to a modern, composable Payments Hub
- SWIFT, SEPA, and T2 payments now processed on Mambu
WESTERN UNION
About the customer
The Western Union Company is committed to helping people around the world who aspire to build financial futures for themselves, their loved ones and their communities.
Their leading cross-border, cross-currency money movement, payments and digital financial services empower consumers, businesses, financial institutions and governments—across more than 200 countries and territories and over 130 currencies—to connect with billions of bank accounts, millions of digital wallets and cards, and a global footprint of hundreds of thousands of retail locations.
The company’s goal is to offer accessible financial services that help people and communities prosper.
In 2022, Western Union launched Western Union Digital Banking
A mobile-first digital banking app focused on the needs of globally mobile individuals. Now available in Germany, Italy, Romania and Poland the app offers multicurrency wallets, debit cards, international transfers, savings features and localised account functionality.
The challenge
Transforming the customer relationship
As customer expectations shifted and competition from fintechs intensified, Western Union expanded its omnichannel capabilities to deliver a new digital banking offering for its current customers and attract new ones. Legacy systems aren’t generally built for the kind of agility or scalability required to launch and operate a full-service digital bank across multiple regions.
The company needed a composable, cloud-native core that would allow it to quickly develop and launch multi-currency accounts, savings products, debit cards, and real-time money transfers. It also had to integrate easily with third-party fintech services while meeting varying regulatory demands. Crucially, the new platform had to support multi-market rollouts with minimal duplication of effort.
The ambition was to develop a native mobile app where customers can open accounts in minutes, select a subscription model and start saving and spending straight away.
“We’ve focused on getting the right product-market fit rather than scaling prematurely. The priority has been building the foundation so that, when we do invest in growth, we’re targeting the right customers with a product that delivers long-term value.”
— Head of Digital Banking (Europe), Western Union
Ambitions beyond the app: modernising payments infrastructure
To fully empower its retail banking business in Europe, Western Union faced a significant infrastructure challenge: they needed a modern, agile SEPA gateway. The existing legacy payment hub was becoming increasingly complex to maintain and lacked the flexibility required for a modern digital bank.
With the European Payments Council’s rule changes looming, relying on legacy technology posed a risk to both compliance and customer experience.
Western Union needed a unified, standards-based solution that could:
- Eliminate integration overhead: avoid the heavy maintenance and technical complexity of direct scheme connectivity with a fully managed solution for SWIFT, SEPA, and TARGET2 (the European real-time gross settlement system).
- Ensure instant compliance: seamlessly adapt to new mandates like Verification Of Payee (VOP) and the Instant Payment Regulation (IPR) without requiring massive internal development cycles.
- Centralise operations: move away from fragmented legacy processes to a single, scalable hub that could handle high transaction volumes with end-to-end automation.
The solution
Modern core and payments, built for flexibility
In 2020, Western Union selected Mambu as the core banking platform for its new digital banking initiative—underpinned by Amazon Web Services (AWS) and integrated with key partners such as Marqeta (card processing) and Outsystems (Front end).
Mambu’s cloud-native, API-first architecture enabled the team to complete the build and launch the greenfield offering in just seven months. The digital bank went live in Germany and Romania in early 2022, followed by Poland and Italy later that year.
Mambu’s deposits and daily banking engine now powers account management, multi-currency functionality and sub-account logic across all four markets. A low-code front end and internal API platform added delivery speed and simplified fintech integrations, while maintaining the flexibility needed to support future products and features.
Beyond the retail initiative, Western Union also partnered with Mambu through its Austrian entity to migrate from Oracle Flexcube to Mambu’s core banking platform in early 2022. By adopting this best-of-breed approach and state-of-the-art technology, Western Union became nimbler and more flexible in delivering business banking services.
Building on this success, Western Union extended the partnership in the spring of 2025 to modernise its payment infrastructure.
They replaced their legacy payment hub with Mambu Payments. This move provided a modern Payments Hub and Verification Of Payee (VOP) functionality, ensuring timely alignment with the European Payments Council’s 2025 rulebook updates.
Working with a focused squad of engineers, Western Union closed approximately 15 product gaps in just six months.
“Mambu was just the right partner for us based on scale of geographic reach and understanding of the local context. Almost everything we do in the product touches Mambu in some form or fashion.”
- Head of Digital Banking (Europe), Western Union
The result
Driving swift market entry and sustainability growth
Since launch, the app has evolved significantly. Mambu’s support for complex multi-currency and sub-account logic has helped Western Union to respond to evolving customer needs and regulatory requirements without slowing down product development.
From multicurrency wallets to savings products and beyond, Mambu supports every layer of the user-facing functionality behind the app.
The benefits are evident from the faster pace of change that Mambu allows with the ability to extend into new features and new markets without starting from scratch. For example, in late 2024, local IBANs were quickly introduced in Germany and Italy—backed by Mambu’s flexible core. Customers who received a local IBAN were more likely to deposit their salary into the app.
“Integrating our app with our retail channel is really important for our customers—to give them that single kind of omni-channel experience. The closer we are to the customer in terms of local events, the closer we are to becoming that primary bank account, that primary relationship. And yes, Mambu is a core piece of the product.”
— Head of Digital Banking (Europe), Western Union
Accelerated, modern and transparent payments
“Mambu Payments fulfilled our criteria for a truly lean and standards-based solution that integrates effortlessly with our systems and is built for modern interoperability. The platform provides us with a seamless, scalable and secure basis to allow us to operate at scale and tailor our services to meet the unique needs of our local customers.”
— Gerald Hentschel, Head of Technology, Western Union International Bank
On the payments side, the impact has been immediate. Just six months after the project officially started, Mambu began processing all of Western Union's SWIFT, SEPA credit, SEPA instant, SEPA direct debit, and TARGET2 payments, alongside VOP requests—resulting in the full decommissioning of its legacy systems by the end of November 2025.
This modernisation across Western Union Bank and three European branches (Austria, Germany, Italy) has replaced a multi-year legacy system with end-to-end automation, securing a future-proof foundation for sustainable growth.
Composable banking beyond core
Mambu now offers advanced payment capabilities alongside a powerful cloud-native banking platform, accelerating time to market for distinctive financial experiences.
