Case Study: Transforming Passport Services by Unlocking the Power of Data

Over the last five years, the Home Office (HO) has partnered with Kainos and BAE Systems to deliver one of the most ambitious government data transformations ever undertaken: the creation of a best in class, cloud-native Passport Data Service (PDS). 

More than 1 billion passport records were migrated with zero disruption to live services, enabling a modern, scalable, data-driven platform that reduces operational complexity by more than 50%, and unlocking the potential for use of this of this trusted identity data. 

The result is a secure, future-proof platform that positions His Majesty’s Passport Office at the forefront and ready to support emerging government ambitions. 

• 1+ billion records migrated seamlessly 
• 50%+ reduction in operational complexity 
• 0 downtime during cutover 
• 20 million transactions processed in the first two weeks – now over 800 million (Aug 26) 
• Data securely available to 140+ areas of government and public bodies 
• Green mark certified – with an 88% reduction in carbon emissions 

The UK Home Office oversees one of the UK’s most significant data registries. But legacy systems - rigid, centralised, and dependent on batch processes - limited how this data could be used: 

• Citizen services relied on tightly coupled processes 
• Innovation was restricted by outdated technology 
• Operational teams were burdened by manual work and ageing infrastructure 

To meet rising demand and enable modern digital identity services, the Home Office needed to modernise its data foundations without disrupting its critical national service. 

Kainos and the Home Office worked together to deliver a full-scale migration to a secure, serverless, cloud-native platform built on AWS. This was not a like-for-like replacement - it was a reinvention of the Home Office’s entire data operation. 

Modern, serverless architecture 

• Introduced GraphQL APIs, AWS Lambda and event-driven data patterns 
• Replaced batch processing with real-time data services 
• Improved responsiveness, resilience, and transparency 

Best in class data foundations 

• Single, authoritative source of passport data 
• Complete auditability, rollback, and real-time monitoring 
• Standardised APIs for consistent onboarding of new data consumers 

Live service transformation with zero disruption 

• Migration rehearsed extensively with risk-mitigated cutover 
• More than 1 billion records transitioned with full data integrity 
• Maintained uninterrupted passport services throughout 

A new operating model 

• Multidisciplinary, outcome-driven delivery teams 
• Modernised governance and more autonomous release cycles 
• The Home Office now fully owns its data and platform 

1.  Faster, more reliable citizen services

New APIs deliver real-time access to application and case data, improving speed and reliability for millions of users. 

2. Reduced complexity

50%+ reduction in manual and fragmented data operations 

3. Cross-government data sharing at scale

Passport data is shared via PDS with over 140 areas of government and public bodies, helping to power major national initiatives: 

• GOV.UK One Login 
• Contactless borders  
• Enhanced identity verification 
• Advanced passenger checks 

4. A foundation for continuous innovation

The new platform enables use cases previously impossible under legacy systems, including: 

• Real-time fraud detection and risk modelling 
• Support for initiatives like the GOV.UK Wallet 
• Streamlined cross-government collaboration 

In short, the Home Office can now adapt quickly, innovate safely, and build confidently for the future. 

“Kainos’ relentless curiosity challenged us to think differently about what good could look like. Combined with their technical expertise, innovation, and user focus, it enabled us to create a resilient and scalable service, built for long-term sustainability and delivering real value to the people who rely on it.” 

- Catherine Walden, Digital Director, Passports, Citizenship and Civil Registration, UK Home Office 

We deployed specialist teams to overcome high-risk challenges, governed delivery through a rigorous model to protect live operations and executed a flawless multi-day cutover without impacting citizens - proving that legacy replacement at scale can be achieved securely, iteratively, and without compromising critical services. 

But this was far more than a successful migration - it was a strategic leap forward. The new Passport Data Service now powers faster applications, better citizen experiences, and seamless collaboration across government.  

The Home Office now fully owns its platform, its data, and its digital future. And with Kainos and BAE as a long-term partners, this transformation is not an endpoint - it is the foundation for continuous innovation, and the beginning of what is possible for one of the UK’s most valuable sets of identity data. 

Find out more about the passport data story here.