Finance teams are used to owning the annual report. As the Corporate Sustainability Reporting Directive (CSRD) brings sustainability disclosures into the annual report — alongside financial statements and subject to the same limited assurance — finance teams are increasingly expected to own sustainability data too. The instinct is to reach for Excel. That’s the wrong move.

This article explains why spreadsheets are structurally unsuited to sustainability reporting under CSRD, and what companies should use instead.

The problem with spreadsheets for CSRD

Spreadsheets work for financial reporting because financial data is relatively structured, comes from controlled systems, and follows well-established conventions. Sustainability reporting under CSRD is fundamentally different:

• Data is decentralized: CSRD data comes from HR, operations, procurement, legal, and supply chain — not from a single accounting system
• Methodology matters: Every GHG emissions figure requires documentation of the calculation method, emission factor source, and data quality
• Audit trail is mandatory: Limited assurance requires traceable evidence for every metric. A spreadsheet cannot provide this at the required level of rigor
• Version control is critical: Multiple contributors updating spreadsheets creates errors, overwrites, and inconsistencies
• The ESRS evolve: Amended ESRS require constant updates to what is mandatory vs. optional. A spreadsheet has no awareness of this

What CSRD audit readiness actually requires

When your sustainability statement goes to limited assurance, your auditor needs to:

• Verify that each quantitative metric is traceable to a source document
• Confirm that calculation methodologies meet the relevant standards
• Check consistency between the sustainability statement and financial reporting
• Assess whether materiality decisions are documented and defensible

None of this is feasible with a spreadsheet-based system. The audit trail doesn’t exist, the methodology documentation is informal, and the traceability from disclosure to source data is missing.

What finance teams should ask for instead

Purpose-built CSRD platforms solve these problems by design. Key capabilities to look for:

• Linked evidence: every metric traceable to its source document
• Calculation audit trail: emission factors, methodologies, and data quality flags documented automatically
• ESRS-aligned templates: structured collection for each ESRS standard, updated to reflect the latest ESRS requirements
• XBRL export: machine-readable output for filing
• Multi-user workflow: assignment of data collection tasks with version control

For finance teams evaluating options, see our guide to top carbon accounting and CSRD software tools.

How Coolset replaces the spreadsheet

Coolset is built for finance and sustainability teams that need CSRD-grade rigour without enterprise complexity. The platform provides all the capabilities above in a system designed for mid-market teams. Every data point has a source, every calculation has a methodology, and every disclosure is auditable from day one.

Book a demo to see how it works.