Legacy core platform constraints
COBOL-era cores limit product flexibility, slow API integration, and create single points of failure. Modernisation must be sequenced to protect processing integrity while progressively unlocking capability.
Banking
Modernising the Engine Room of Banking
Banks are caught between the weight of legacy infrastructure and the speed demanded by Open Banking, real-time payments, and digital-first customer expectations. SurreyTech delivers core platform modernisation that protects processing integrity while unlocking the agility banks need to compete.
Core to channel
From mainframe modernisation to mobile banking, delivered with processing integrity.
Industry Context
Banking infrastructure is being rebuilt from the core outward.
The UK banking sector is in the middle of a generational technology shift. Established banks are migrating away from mainframe-era core platforms while simultaneously building Open Banking capabilities, real-time payment processing, and digital onboarding journeys. Challenger banks and Banking-as-a-Service providers are raising the bar on customer experience and time-to-market. The institutions that modernise their technology foundations fastest will define the next decade of UK banking.
The core banking dilemma
Most established UK banks still run critical processing on platforms designed in the 1980s and 1990s. These systems work, they process millions of transactions daily with remarkable reliability, but they constrain every other technology initiative. API integration is slow. Product configuration is rigid. Regulatory reporting requires complex extraction and reconciliation.
Replacing core banking platforms is among the most complex technology programmes any organisation undertakes. The data migration alone involves billions of records with decades of accumulated business logic. Parallel running periods must demonstrate processing equivalence before cutover. And the bank must continue operating throughout.
SurreyTech has delivered core banking transformation at institutions where failure would have systemic consequences. We understand the sequencing, the risk controls, and the governance rigour these programmes demand.
Core banking replacement demands precision in data migration, parallel running, and cutover planning.
Key Challenges
The transformation pressures shaping banking technology decisions.
Open Banking and PSD2 obligations
Regulatory mandates require secure API access to account data and payment initiation. Beyond compliance, Open Banking creates strategic opportunities for banks that build genuine ecosystem capabilities.
Real-time payments infrastructure
Faster Payments, CHAPS renewal, and the New Payments Architecture demand modernised payment processing, clearing, and settlement capabilities. Batch-era infrastructure cannot support real-time expectations.
Digital customer experience
Mobile banking, digital onboarding with identity verification, and personalised financial management are now baseline expectations. Banks competing for digitally native customers must match fintech-grade experiences.
Basel III.1 and regulatory capital
The PRA's implementation of Basel III.1 standards requires banks to overhaul risk-weighted asset calculations, credit risk modelling, and capital reporting infrastructure by January 2027.
Cloud adoption and concentration risk
Migrating banking workloads to cloud requires addressing PRA expectations on third-party concentration, operational continuity, and exit planning. Multi-cloud strategies add architectural complexity.
How We Help
End-to-end delivery capability for banking transformation programmes.
Core banking transformation
We deliver core banking replacement and modernisation programmes from vendor selection through data migration, integration build, parallel running, and cutover. Our teams have direct experience with Thought Machine Vault, Temenos Transact, Mambu, and FIS Modern Banking Platform. We bring the data migration methodology, testing rigour, and cutover planning that these high-stakes programmes require.
Open Banking and API platform delivery
We design and build Open Banking API platforms that go beyond PSD2 compliance to create genuine ecosystem value. This includes API gateway architecture, consent management, strong customer authentication (SCA), and third-party provider onboarding. We help banks position Open Banking as a growth channel rather than a regulatory cost.
Digital banking channels
We deliver mobile banking applications, digital onboarding journeys with eKYC and identity verification, and personalised customer engagement platforms. Our approach connects channel experiences to core banking capabilities through clean API integration rather than screen-scraping legacy interfaces.
Payments modernisation
We help banks modernise payment processing infrastructure for real-time capabilities, ISO 20022 message standards, and the emerging New Payments Architecture. This includes payment hub implementation, clearing and settlement integration, and fraud detection capabilities that operate at transaction speed.
Regulatory and compliance delivery
From Basel III.1 capital calculation overhauls to SM&CR accountability mapping, we deliver regulatory change programmes that embed compliance into banking operations. Our teams understand both the regulatory intent and the technology implementation required to satisfy supervisory expectations.
Relevant Services
Banking programmes typically draw on multiple SurreyTech capabilities.
Ready to discuss your banking transformation?
Whether you are replacing a core banking platform, building Open Banking capabilities, or modernising payment infrastructure, we bring the delivery depth these programmes demand.
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