For many UK and Ireland finance teams, spreadsheet-based lease accounting has been the default approach for years. It requires no significant upfront investment, uses tools the team already knows, and for organisations with a small or stable lease portfolio, it has often been workable. 

Revised FRS 102 changes that equation. From accounting periods beginning on or after 1 January 2026, most leases will need to be recognised on the balance sheet as right-of-use assets and lease liabilities. The result is a more active, ongoing accounting process requiring consistent calculations, documented assumptions, regular reassessments, and audit-ready outputs across the full lease lifecycle. 

The key question is not whether spreadsheets can handle lease accounting in principle. The question is whether they can support that kind of controlled, repeatable process as complexity grows. 

Why Spreadsheets Became Common for Lease Accounting 

Spreadsheets became the default tool for lease accounting for practical reasons. 

• Widely available and familiar to finance teams 
• Flexible enough to build custom lease models without specialist software 
• Low upfront cost compared with dedicated systems 
• Manageable for smaller portfolios or where lease accounting was mainly an annual disclosure or reconciliation exercise 

The previous FRS 102 lease accounting model did not demand the same level of ongoing data governance, calculation frequency, or audit trail documentation the updated FRS 102 requires. For many organisations, a well-maintained spreadsheet was proportionate to the reporting obligation. 

Why Revised FRS 102 Increases Pressure on Spreadsheet-Based Lease Accounting 

Revised FRS 102 fundamentally changes the nature of the task. 

Where lease accounting was previously a periodic exercise for many organisations, it now becomes a more active balance sheet process. Finance teams will need to recognise and maintain lease liabilities and right-of-use assets, apply consistent assumptions across the portfolio, account for modifications, reassessments, and lifecycle events, and produce reliable, auditable outputs within tighter reporting timelines. 

For spreadsheet users, calculation frequency increases, history needs to be preserved, and the margin for undocumented manual changes narrows considerably. Discount rates, lease terms, extension options, and reassessment triggers all require consistent treatment and traceable justification. 

The revised standard does not break spreadsheet-based lease accounting overnight. It exposes weaknesses that may have been sustainable under a simpler model. 

Common Spreadsheet Risks in Lease Accounting Compliance 

The risks of relying on manual spreadsheet models are not theoretical. 

As portfolios grow, spreadsheet models grow with them. Additional leases mean more rows, more calculation logic, more formula dependencies, and more manual maintenance. When a lease is modified, extended, or terminated, the finance team must recalculate the lease liability from the correct effective date while preserving the full history of prior calculations for audit and reporting purposes. Over time, spreadsheets become progressively harder to manage and verify. 

Common warning signs that a spreadsheet-based approach is under strain include: 

• Multiple spreadsheet versions in circulation 
• Broken or overwritten formulas from manual updates 
• Inconsistent methodologies across entities or asset types 
• Manual workarounds for modifications and reassessments 
• Fragmented or absent audit trails 
• Difficulty reproducing prior-period calculations 
• Month-end and year-end delays 
• Reduced confidence in outputs when team members change 

Key-person dependency is a particular concern. If FRS 102 lease accounting depends on one or two individuals who understand the spreadsheet’s structure, staff changes can become a governance risk with limited notice. 

The Hidden Operational Costs of Spreadsheet Lease Accounting 

The time and resource burden of managing leases manually builds in ways that are easy to underestimate. 

Staff time spent maintaining, reviewing, correcting, and validating spreadsheet models is time diverted from other finance priorities. Supporting auditors through manual evidence preparation adds further demand. Additional review cycles arise from calculation errors or undocumented assumptions. The more complex the portfolio, the more the process absorbs. 

Several studies have estimated that 80–90% of business spreadsheets contain some form of error, with risk increasing as models become larger, more manual, and more operationally complex. Full source references are listed at the bottom of this article.These figures matter particularly for FRS 102 lease accounting, where a missed modification, an incorrect discount rate, or an overwritten formula can affect reported balances, audit outcomes, and comparative figures across multiple periods. 

The cost of maintaining a complex lease spreadsheet often exceeds initial expectations. The time spent creating, updating, and checking lease profiles, recalculating modification dates, and preserving calculation histories adds up. When reporting timelines are under pressure, those costs become difficult to absorb. 

How Purpose-Built Lease Accounting Software Improves Control and Efficiency 

Purpose-built lease accounting software addresses the core weaknesses of spreadsheet-based approaches directly. The table below sets out how the two compare across areas most relevant to revised FRS 102. 

This comparison highlights a fundamental shift. As lease accounting becomes more complex under revised FRS 102, finance teams require systems that provide control, consistency, and auditability—areas where manual spreadsheet processes often fall short. 

Why Lease Accounting Software Is Becoming More Important Under Revised FRS 102The updated FRS 102 model is manageable. However, it places greater operational demands on finance teams, and spreadsheet-based processes that once worked may no longer keep pace.  

The hidden costs of spreadsheet lease accounting accumulate over time: staff hours, audit support, manual corrections, version control failures, and key-person dependencies. Purpose-built lease accounting software replaces these recurring costs with a more controlled, consistent, and auditable way of managing leases across the full portfolio. 

OneTouch Leasing is a purpose-built lease accounting platform designed for UK and Ireland businesses navigating the revised FRS 102 environment. It replaces large, manual spreadsheet models with a flexible, user-controlled system that fits around existing finance processes and supports accurate, audit-ready reporting as portfolios evolve. 

References 

Study finds 94% of business spreadsheets have critical errors – https://phys.org/news/2024-08-business-spreadsheets-critical-errors.html 

88% of the Excel spreadsheets have errors – https://www.cassotis.com/insights/88-of-the-excel-spreadsheets-have-errors 

Spreadsheet errors can have disastrous consequences, yet we keep making the same mistakes – https://theconversation.com/spreadsheet-errors-can-have-disastrous-consequences-yet-we-keep-making-the-same-mistakes-219356