UK Open Banking passes billion payments & 100bn API calls

The UK's Open Banking ecosystem has passed one billion payments and 100 billion API calls across the CMA9 banks, marking twin milestones more than eight years after launch.

Data from Open Banking Limited also showed record monthly API traffic of 2.81 billion calls in June and 40.16 million Open Banking payments during the month. Average response times fell to 349 milliseconds, while weighted availability reached 99.80%.

The latest figures point to continued use of account-to-account payment services and data-sharing tools built on the Open Banking framework. The CMA9 group includes the UK's nine largest banks and building societies by personal and business current account volumes: AIB Group, Bank of Ireland, Barclays, HSBC, Lloyds, Nationwide, Northern Bank, NatWest and Santander.

Monthly API traffic rose 4.4% from the previous month to its highest level so far. Payment volumes were broadly steady despite a 1.2% fall in Single Domestic Payments to 32.43 million.

That decline was offset by growth in Sweeping Variable Recurring Payments, or sVRPs, which rose 6.7% month on month to 7.73 million. Variable Recurring Payments allow customers to give ongoing consent for repeated payments, and growth in that category suggests wider use of a newer part of the Open Banking model.

User connections, a measure of active consents between customers and services, fell 4.2% to 18.81 million in the latest monthly data. Even so, broader trends in transactions and API volumes suggest usage remains high across the ecosystem.

Operational trends

Performance data showed improvements in speed as well as scale. The average time for a provider to respond to a payment request improved by 50 milliseconds from the previous reporting period.

Unweighted availability was 99.35%, alongside the higher weighted availability figure. Banks, fintech firms and merchants watch those metrics closely because delays or outages can disrupt payment journeys and access to financial data.

Open Banking was introduced in the UK to require major banks to provide standardised access to account data and payment initiation services through application programming interfaces, subject to customer consent. The framework has since become a core route for fintech firms and other providers to build services on top of current accounts.

Use cases range from personal finance apps and lending checks to direct account-based payments for shopping, bills and transfers. The one billion payments milestone reflects growth in payment initiation, often seen as a longer-term development than account information services.

Market position

The UK was one of the earliest large markets to implement Open Banking at scale, initially following a competition remedy linked to the retail banking market. Industry participants have long argued that common technical standards and bank participation rules have given the country a lead over many other jurisdictions.

At the same time, the sector has faced questions about commercial models, long-term governance and how to extend Open Banking into a broader Open Finance framework. The latest milestones come as policymakers and market participants continue to debate how to sustain the system beyond its original implementation phase.

Henk Van Hulle, Chief Executive Officer of Open Banking Limited, said: "These milestones reinforce the UK's position as a global leader in Open Banking and demonstrate an ecosystem that continues to scale in both volume and capability. As adoption increases and new use cases emerge, Open Banking will play an increasingly vital role in supporting competition, innovation and growth across the UK's financial services landscape.

"As we look ahead, our focus remains on building on these achievements. By continuing to strengthen resilience, performance and innovation, we can unlock even greater value for consumers, businesses and the wider economy, while supporting the next phase of the UK's Open Banking and Open Finance journey."

The figures suggest the network is handling larger volumes while maintaining high uptime across the main institutions. For providers that depend on the APIs to collect account data or initiate payments, that mix of scale and reliability is central to wider adoption.

Growth in Variable Recurring Payments is also likely to draw attention, as many in the sector see the model as one of the more practical extensions of Open Banking payments. It offers a way to automate repeated transfers from bank accounts without relying on cards, while giving customers consent controls.

Single Domestic Payments still account for most monthly Open Banking payment traffic, at 32.43 million of the 40.16 million total. But the faster growth rate in sVRPs shows where some of the market's momentum now lies.

Crossing 100 billion API calls underlines the extent to which Open Banking has become part of the plumbing of UK retail financial services. Monthly traffic of 2.81 billion calls and payment volumes above 40 million show the system is now operating at a scale far beyond its early years.