Standardisation Challenges Within UK Open Banking Ecosystems

Introduction 

Open banking was initially hailed as a quantum shift, but today it has become the foundation for modern financial services.  With more than 16 million active users and rapid growth in payment volumes, it is now a core part of the financial services industry. Open Banking has enabled real-time data flows, transformed credit assessment and catalysed innovation across the board. Yet behind this progress lies a persistent challenge: standardisation. 

At its core, Open Banking was designed to create a level playing field, allowing third-party providers to access bank data securely and build innovative services. The vision was clear: enhanced competition, improved customer outcomes, and a thriving ecosystem of open banking solutions. However, as adoption accelerates, inconsistencies in standards, data structures, and governance have become increasingly visible. 

For organisations building or scaling SaaS solutions or fintech platforms, these inconsistencies directly impact cost, performance, and user experience. 

The Fragmented Reality Behind a Unified Vision 

The UK is often considered a global leader in open banking, thanks to early regulatory intervention by the Competition and Markets Authority (CMA). The initiative was explicitly designed to “increase innovation and competition” in retail banking. 

However, standardisation has not kept pace with ecosystem growth. While the Open Banking Implementation Entity (OBIE) established baseline API standards, real-world implementation varies substantially across banks. 

This creates three immediate challenges: 

• Inconsistent API performance across providers  
• Diverging data formats, especially in transaction categorisation  
• Uneven uptime and latency, affecting real-time use cases  

For fintechs and banks alike, this means building multiple integrations for what should be a single standard. In practice, every additional bank connection introduces new edge cases—undermining the promise of a seamless open accounting data environment. 

Data Standardisation: The Weakest Link 

One of the most persistent issues is the lack of uniformity in financial data itself. While APIs may follow a shared specification, the underlying data returned often differs in structure and quality. 

For example: 

• Transaction descriptions are not consistently formatted  
• Merchant categorisation varies widely  
• Balance calculations can differ depending on pending transactions  

This creates friction for any financial data management system attempting to deliver accurate insights. 

Recent research highlights that while open banking enables richer datasets, inconsistencies in data integrity and validation remain a core risk in implementation models. 

For developers, this translates into additional layers of normalisation logic which add complexity, cost, and potential breaking points. For end users, it can result in misleading dashboards or incomplete financial insights. 

Regulatory Complexity and Evolving Governance 

Standardisation challenges are not purely technical; they also come with regulatory consequences. The UK’s open banking framework continues to evolve, with new legislation expected to give regulators stronger oversight and rule-setting powers. 

While this is a positive step toward long-term stability, it introduces short-term uncertainty: 

• Multiple regulatory bodies influence OA and OB standards (FCA, CMA, Treasury)  
• Governance transitions, from OBIE to future entities, remain dynamic  
• New concepts like open finance expand the scope beyond banking  

Government updates have already highlighted the importance of strengthening governance structures to ensure consistency and long-term success. 

Open banking and open accounting now power far more than payments and embedded lending. They power predictive cash flow insights, automated finance operations, fraud detection, and highly personalised financial experiences, including accounts receivable solutions. 

They also support emerging capabilities like portable financial identity, SME financial management, and subscription tracking, all built on shared open accounting data. 

However, the wider these use cases grow, the more inconsistent standards across an open banking platform limit accuracy, scalability, and user experience.  

Pulse is a strong example of how fintech platforms are addressing the challenges within open banking ecosystems. By leveraging Open Banking and Open Accounting alongside AI and ML, Pulse powers solutions across cash flow forecasting, accounts receivable management, Business Insights, and its embedded lending ecosystem, the Unified Lending Interface (ULI). 

Pulse helps normalise and structure data from multiple open banking sources, reducing the impact of inconsistencies and simplifying integration for lenders and fintechs. This allows organisations to work with more consistent, usable data without needing to build complex normalisation layers themselves. With security and compliance built in, and a focus on streamlining data flows, Pulse enables banks, lenders, aggregators, and SMEs to operate more efficiently within an otherwise fragmented ecosystem. To learn more about Pulse and its solutions, contact us today. 

The Shift Toward Open Finance, and More Complexity 

The UK is now moving beyond open banking toward open finance, extending data sharing to savings, investments, pensions, and insurance. 

While this expansion promises richer use cases, it also magnifies existing challenges: 

• More data types to standardise  
• More stakeholders to coordinate  
• Greater need for interoperable frameworks  

The Financial Conduct Authority has already emphasised the need for a structured transition, balancing innovation with risk management. Without stronger standardisation, scaling an open banking platform into open finance could amplify fragmentation rather than resolve it. 

What Better Standardisation Could Look Like 

To move forward, the UK ecosystem needs to shift from baseline compliance to true interoperability. 

Key priorities include: 

• Uniform data schemas across all providers  
• Consistent API performance benchmarks  
• Standardised consent and authentication journeys  
• Clear commercial frameworks for premium APIs  

Collaboration is equally important. Banks, lenders, and regulators must align on shared outcomes, and not just shared specifications. 

For organisations investing in open banking solutions or building systems that rely on OA or OB data feeds, the focus should be on flexibility. The goal is to build systems that can absorb inconsistency while preparing for future standardisation. 

Conclusion 

The UK’s open banking journey is a success story, but an incomplete one. Adoption is rising, innovation is accelerating, and the foundations are strong. Yet standardisation remains the ecosystem’s biggest constraint. 

For banks, inconsistent standards increase operational burden. For lenders, they slow down credit decisions. For SMEs, they create friction in what should ideally be a seamless financial experience.  

As the UK moves toward open finance, the stakes are even higher. Without stronger alignment in data, APIs, and governance, the ecosystem risks fragmentation at scale. The next phase of growth will not be driven solely by new features, but by how effectively the industry can standardise what already exists. Only then can the full potential of any open banking platform and the broader vision of a connected financial ecosystem be realised.