How to Build a CSRD Reporting System from Scratch

Introduction

Starting your CSRD reporting system from zero may seem overwhelming — especially if you’re a small and growing business (SME) without a sustainability department. Yet, building an internal system doesn’t have to mean buying expensive software or hiring consultants. You can build a robust CSRD reporting system without consultants using existing data and simple tools. With the right structure, you can create a practical, scalable solution that meets the Corporate Sustainability Reporting Directive (EU) 2022/2464 requirements.

This guide walks you through how to design a CSRD system that works for your company size, budget, and existing data setup — from defining what to report to setting up a basic digital workflow.

Step 1: Map Your Reporting Obligations

Before building anything, clarify what you actually need to report. Under the CSRD and related European Sustainability Reporting Standards (ESRS), companies must disclose both environmental and social information — but the scope depends on your size and whether you’re listed.

For small and growing businesses, even if you’re not directly in scope, your customers or lenders may still request sustainability data. Use the VSME Standard to align with the same reporting logic as larger firms but on a proportionate scale.

Quick checks:

• Do you meet the CSRD thresholds (250+ employees, €40M+ turnover, €20M+ balance sheet)?
• Are you part of a larger group or supply chain that reports under CSRD?
• Do you plan to apply the VSME Basic or Comprehensive module?

See which module fits your company →

Step 2: Identify Core Data Streams

Your reporting system will only be as good as your data collection structure. Start by identifying where sustainability data already exists:

Create a central list of data owners in your company (e.g. facilities manager, HR, finance) and set quarterly reminders for updates.

Learn how to collect sustainability data efficiently →

Step 3: Design Your Data Storage and Structure

Once you know what to track, you need a simple but organised data architecture. You can start with:

• A central folder structure (e.g. Google Drive, OneDrive, or SharePoint)
• A spreadsheet or database with clear column headers (metric, period, source, verification)
• Shared templates for all departments

Each data entry should include:

• Metric name (e.g. Energy use – Scope 2)
• Unit (kWh, m³, kg)
• Period covered
• Source document or file path
• Verification status

This ensures traceability and supports audit readiness, one of the CSRD’s key assurance principles.

Check our guide on fuel receipts and invoice tracking →

Step 4: Automate Where It Matters Most

Once your manual system works, identify bottlenecks and automate gradually:

• Use APIs or automated imports from accounting, HR, or ERP systems.
• Apply formulas or scripts to calculate GHG emissions or waste intensity.
• Consider CSRD reporting tools that offer templates, dashboards, and audit trails.

Automation not only reduces human error but also helps maintain consistent data for the ESRS format, making assurance easier later on.

Compare manual vs software CSRD reporting →

Step 5: Integrate with Your Annual Reporting Cycle

CSRD reporting should integrate with your financial and management reporting timeline. Synchronise sustainability data collection with your financial close process. Assign clear roles:

• Data providers: Department heads supplying metrics
• Reviewers: Sustainability or finance leads validating accuracy
• Approver: Management sign-off for publication

Even if you’re using spreadsheets today, this structure will scale naturally when you transition to software.

Step 6: Prepare for External Assurance

The CSRD requires limited assurance for sustainability data. That means external reviewers must trace how figures were calculated and verified. Having a clear data lineage — from source to published number — can cut assurance costs and reduce rework.

Store all supporting documents (e.g., utility bills, payroll exports) with consistent file names and timestamps. When your reporting grows, assurance-ready tools can automate this traceability.

Understand CSRD assurance expectations →

Frequently Asked Questions

Do I need software to build a CSRD reporting system?

Not initially. Many small and growing businesses (SMEs) start with spreadsheets and shared drives, as long as they maintain version control and traceability. Over time, however, software becomes essential to handle data volume and ensure compliance with ESRS.

Compare manual vs automated reporting options →

What’s the most common mistake when setting up a CSRD system?

Skipping documentation. Even small and growing businesses (SMEs) forget to record where data came from or how it was calculated. Without an audit trail, assurance becomes costly or even impossible later.

Learn how to document data sources properly →

How can I make my reporting system scalable?

Build your structure around standard data types (energy, water, workforce) and ensure everything is stored consistently. When you later adopt a reporting tool, your data will integrate seamlessly.

See how automation supports CSRD scalability →

Key Terms

• CSRD: Corporate Sustainability Reporting Directive — EU law requiring sustainability disclosures.
• ESRS: European Sustainability Reporting Standards that define the structure and content of CSRD reports.
• VSME: Voluntary Sustainability Reporting Standard for SMEs, providing a simplified framework.
• Data lineage: The documented path showing where and how data was generated, processed, and verified.
• Assurance: Independent validation confirming the accuracy of sustainability data.

Conclusion

Building a CSRD reporting system from scratch is less about technology and more about structure. Start simple, map your data sources, and document everything. Then automate gradually as your needs grow. A well-built system not only ensures compliance but also gives your business a strategic edge — enabling you to make better, data-driven sustainability decisions.

Explore tools that simplify CSRD reporting →

To help you get started, use our interactive checklist generator to create a customised data collection checklist based on your company’s specific needs:

This tool will help you identify all the data points you need to collect and organise them into a structured checklist that fits your reporting system.