Supporting the fifth largest building society in the UK
Founded in 1875, Leeds Building Society has launched its pilot digital savings product on Mambu’s cloud-native platform as part of its multi-year core modernisation to better serve its one million members.
- months to go-live
- million members
- billions in assets managed
Leeds Building Society
About the customer
Leeds Building Society is the UK’s fifth-largest building society and operates as a mutual, meaning it is owned by its over one million members across the UK. Established in 1875, it has been helping members to save money and buy a home ever since. This is still at the heart of its purpose – to put home ownership within reach for more people, generation after generation.
Recent initiatives include stopping lending on second residential homes, launching products and services specifically for first-time buyers and advocating for housing and planning policy reform.
It has invested in its business and the same time as delivering for its members and communities, consistently paying above market average levels of interest to savers, raising millions of pounds for charities and donating thousands of hours in workforce volunteering time.
The challenge
Overcoming legacy tech
After operating on a legacy core system for over 20 years, Leeds Building Society faced significant challenges in meeting the evolving needs of its members. To stay competitive and offer more innovative services, the building society recognised the necessity of modernising its tech stack.
With an expanding membership base and a growing demand for digital solutions, Leeds Building Society needed a flexible and scalable platform that would allow them to launch new products quickly, scale services effectively and provide a seamless, quick, and effective financial experience for their members.
“Our partnership with Mambu continues to go from strength to strength. We’ve spent the past year building the engineering foundations for the complete overhaul of our technology and we are delighted to see the technology being used for live savings accounts. These foundations provide the sustainability we need to support our million members and the £30bn of their money we look after, while also giving us the flexibility to continue to help ever more people into home ownership.”
- Rob Howse, Chief Operating Officer at Leeds Building Society
The solution
A modern savings product on the cloud
Leeds Building Society chose Mambu’s cloud-native banking platform as the foundation for its core transformation. In less than a year, the Society successfully launched a pilot digital savings product as the first milestone in its multi-year core modernisation project.
Powered by Mambu’s composable architecture, Leeds Building Society can now offer faster, more flexible services to its members, replacing outdated technology with scalable, cloud-based solutions.
Partnering for success
Accenture is supporting Leeds Building Society in delivering their bold transformation and migration towards Mambu's composable core banking platform. Through a true partnership model, Accenture is complementing the skills within the Society with their core banking, migration and transformation experience enabling their ambition to put home ownership within reach of more people.
The impact
The road to full core modernisation
The launch of the pilot digital savings product is just the beginning. Leeds Building Society has an ambitious roadmap for further core modernisation, with plans to extend the transformation to its mortgage offering. The Society’s continued evolution ensures that it will remain at the forefront of delivering innovative financial services to its members for years to come.
This partnership sets a precedent for digital transformation in the broader building society sector showcasing the industry's shift towards next-generation cloud platforms.
“Partnering with Mambu provides us with a solution that brings the best composable architecture and cloud technology coupled with innovative functionality that matches the very best in the industry. This strategic move will mean we can spend more time improving the lives of our members and less on worrying about our legacy technology. We’re looking forward to the next steps on our journey together.”
- Rob Howse, Chief Operating Officer at Leeds Building Society
Building societies,
step into the future.
step into the future.
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