Nationwide Building Society, the UK’s largest building society and an existing investor in Aveni, has become the first organisation outside of Aveni’s core product suite to deploy the company’s FinLLM in a live environment, marking a significant milestone in the FinTech’s push to commercialise its financial services-specific AI model.
Nationwide is currently running live tests of FinLLM across a range of compliance use cases within financial services, with broader rollout planned across multiple applications once evaluation is complete. The building society has been an investor in Aveni since 2024 and played a hands-on role in shaping the model during its development, contributing to both its technical construction and Aveni’s governance and risk framework.
FinLLM is a family of large language models built specifically for the financial services sector, developed over twelve months by the specialist team at Aveni Labs. The model integrates structured and unstructured data, is built around ethical AI principles, and operates under rigorous governance oversight. It has been aligned with both FCA guidance and the EU AI Act, and extensive benchmarking has shown it consistently outperforms general-purpose models on financial tasks. Unlike broader AI models that approximate regulatory context, FinLLM models are trained directly on the rules, workflows, and supervisory expectations applied to regulated firms.
The family of models approach at the heart of FinLLM allows organisations to select the appropriate model for each specific use case and scale deployments as requirements develop. Each model is fine-tuned for its purpose, spanning agent assurance to compliance detection, and is designed to improve with each deployment.
Aveni develops AI products for banks, wealth managers, and financial advisers operating in the UK. Its flagship products, Aveni Assist and Aveni Detect, are currently powered by FinLLM. Aveni Assist supports adviser and operations productivity, while Aveni Detect provides AI-driven compliance monitoring. The company positions FinLLM as a new benchmark for responsible generative AI in one of the world’s most heavily regulated industries.
Nationwide’s move to deploy the model in production follows its status as a co-creator of FinLLM, having invested in Aveni in 2024 as part of a strategic partnership. The building society’s decision to go live with the technology, rather than simply observe its development, is being framed by both parties as a signal of confidence in the model’s readiness and of Nationwide’s broader commitment to responsible AI adoption.
Nationwide chief data officer Sri Kanisapakkam said, “Since investing in Aveni and working together on co-creating FinLLM, we are delighted to see how it has developed, and even more so to be the first organisation to deploy it. The industry-specific family of models approach that Aveni has taken is exactly what we need: the flexibility to apply the right model for the right task, at scale. We’re excited by the early performance we are seeing during testing and the potential benefits FinLLM will bring both Nationwide and our customers, as we continually look to deliver better service and experience through the responsible adoption of new technologies.”
Aveni CEO Joseph Twigg said, “Nationwide’s decision to be both an investor in and the first commercial customer of FinLLM is a powerful endorsement of what we have built. Their early engagement has been instrumental in shaping a model that truly reflects the needs of a major UK financial institution. The family of models approach we have taken means In an era where AI sovereignty is becoming increasingly important, FinLLM is a fantastic example of UK AI innovation, a highly performant model, with data transparency, AI safety and ethics at its heart, that will start to deliver real automation for a range of use cases across UK financial services.”
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