At the start of 2026, the Financial Conduct Authority launched the Mills Review, a forward looking assessment of the long term impact of advanced artificial intelligence on retail financial services through to 2030 and beyond. Led by FCA Executive Director Sheldon Mills, the review is designed not only to assess how AI may reshape the sector, but to inform how regulation, supervision and firms should prepare for that transformation.
Why the Mills Review Matters
Artificial intelligence has moved rapidly from experimental use cases to core operational capability across financial services. Firms now rely on AI for fraud detection, credit decisioning, customer servicing, pricing optimisation and increasingly personalised financial guidance. The Mills Review recognises that AI is becoming embedded within market infrastructure and customer journeys. It looks beyond current applications towards more autonomous and interconnected systems that could significantly alter competition, market structure and consumer behaviour.
The FCA has made clear that it does not intend to create an entirely new AI rulebook. Instead, it aims to assess whether existing regulatory frameworks, including the Consumer Duty, the Senior Managers and Certification Regime and operational resilience requirements, remain appropriate in an AI enabled environment. This approach reinforces the FCA’s outcomes based philosophy, focused on ensuring markets function well and consumers receive good outcomes, while still enabling innovation.
The review invites input across four broad themes. These include the future evolution of AI technologies, the impact on firms and market dynamics, the implications for consumers and trust, and the future shape of regulation. Importantly, this is not simply a consultation on incremental change. It is a strategic look at how financial services may operate at the end of the decade.
Strengthening AI Governance and Accountability
As AI systems become more sophisticated, questions of explainability, accountability and oversight become central. Boards and senior managers must be able to demonstrate effective governance over AI use cases. Under the Senior Managers and Certification Regime, accountability cannot be delegated to technology alone and a ‘human in the loop’ mode becomes imperative.
Firms will increasingly need to evidence robust model validation, ongoing monitoring, clear documentation and effective challenge. The regulatory expectation will not be limited to technical robustness. It will extend to fairness, customer understanding and demonstrable alignment with the Consumer Duty. This will require significant work that bridges regulatory expertise, technology understanding and assurance capability.
Embedding Consumer Duty at Scale
The Consumer Duty requires firms to act to deliver good outcomes for retail customers and to evidence that those outcomes are being achieved. In an AI enabled environment, outcomes monitoring must be continuous, scalable and data driven. Manual sampling and retrospective review are unlikely to be sufficient where customer journeys are increasingly automated and personalised.
This is where Square 4 Partners, and in particular Assure 4, plays a critical role. Assure 4 builds on Square 4’s award-winning outcomes testing framework and combines regulatory expertise with AI enabled analytics to provide real time monitoring of customer interactions and journeys. As part of a human in the loop managed service, it enables firms to assess key customer journeys at scale, producing audit ready evidence for boards and regulators.
As supervisory scrutiny of AI and automated decision making intensifies, firms that can demonstrate structured, data led assurance over customer outcomes will be significantly better positioned. Assure 4 supports this by providing both insight and defensible evidence, aligning operational efficiency with regulatory confidence.
Engaging Proactively with the Regulatory Agenda
The Mills Review represents an opportunity for firms not only to respond to regulatory expectations but to help shape them. By contributing evidence, sharing practical insights and demonstrating robust governance frameworks, firms will have been able to position themselves as credible and responsible innovators.
Square 4 Partners supports clients in preparing regulatory submissions, reviewing AI governance frameworks and aligning strategic technology deployment with regulatory obligations. This includes board level advisory, gap analysis against evolving expectations and practical implementation support.
Turning Regulatory Change into Strategic Advantage
The Mills Review signals that the FCA is thinking strategically about the future of AI in financial services. For firms that invest early in governance, assurance, and outcomes testing, this will build stronger resilience, deeper customer trust, and a more sustainable competitive advantage.
By combining regulatory expertise and our scalable managed service with technology-enabled assurance, Square 4 Partners is uniquely positioned to help firms navigate this evolving landscape. In an outcomes-based regulatory environment, proactive assurance is not simply about compliance. It is about demonstrating leadership, accountability and long-term value creation, improving both customer and commercial outcomes for customers and firms alike.
