The PRA and FCA expect financial services businesses to operate with fully segregated functions, clear audit trails, no single points of failure, and consistent data across planning and regulatory reporting.

However, reliance on spreadsheets for critical controls remains widespread across the sector.

When it comes to accounting, banks and building societies know spreadsheets aren’t enough.

This is why they choose specialist solutions like Whistlebrook Financials.

Yet beyond core accounting, spreadsheets still prevail in critical areas including business planning, treasury management, asset and liability management (ALM), and Effective Interest Rate (EIR) calculations.

These spreadsheet solutions are often handcrafted by a single individual, undocumented, and opaque. They lack audit trails, consistency checks, and validation. In short, they introduce significant risk. For example, IFRS 9 and FRS 102 require multiple scenarios and assumptions in EIR calculations, something spreadsheets are ill-suited to manage reliably.

Once EIR outputs are set, they must remain transparent, consistent, and inviolable.

The same issue arises in budgeting and planning. Relying on spreadsheets risks basing forecasts on false or inconsistent data.

By contrast, dedicated software solutions bring rigour and control, transforming financial planning from an “art” into a disciplined science. This ensures the assumptions used by treasury, finance, and planning teams align, producing insights from a single, consistent source of truth.

Auditors are increasingly recognising the efficiency and risk mitigation benefits of software over spreadsheets. With integrated systems, there is no discrepancy between the data driving treasury management, financial reporting, or product planning.

Instead, every team works from the same complete and consistent dataset.

The reality is clear: reliance on spreadsheets creates systemic risk.

Regulatory and reporting pressures will only accelerate the shift towards integrated, purpose-built software solutions. For banks and building societies, the strategy must be to ensure that every view of the business is aligned, complete, and consistent.

At Whistlebrook, our suite of modules delivers exactly that, which supports finance, planning, treasury, and regulatory reporting from a single source of truth. For financial services firms, replacing unintegrated spreadsheets is no longer just a best practice; it’s a business-critical priority.

If you would like to learn more about the Whistlebrook modules or request a demo please contact: enquiries@whistlebrook.co.uk | +44 (0)1480 309550