ESRS S1: Reporting on Your Own Workforce Under CSRD

By Sai Shankar, Guest Author

The environmental standards under CSRD have attracted the majority of attention so far, and understandably. Carbon accounting is where most organisations start, and ESRS E1 is where most of the technical complexity lives. But for many companies preparing their first sustainability statement, the social standards will be the harder ones to close out.

ESRS S1, covering own workforce, is the largest and most involved of the four social standards. It touches employment data that sits in HR systems, payroll processes, health and safety records, and diversity monitoring. For companies that have never brought these datasets together for reporting purposes, S1 can be the standard that consumes the most cross-functional time.

What ESRS S1 Actually Covers

ESRS S1 addresses the impacts, risks, and opportunities relating to a company’s own workforce. It is structured around four main topics:

• Working conditions: including secure employment, working time, adequate wages, social dialogue, freedom of association, collective bargaining, work-life balance, and health and safety
• Equal treatment and opportunities for all: including gender equality and equal pay, training and skills development, employment and inclusion of persons with disabilities, measures against violence and harassment in the workplace, and diversity
• Other work-related rights: including child labour, forced labour, adequate housing, and privacy
• Characteristics of the workforce: the demographic breakdown of employees and non-employees, contract types, and geographic distribution

Crucially, the standard covers not only direct employees but also non-employees in the company’s own workforce. This includes self-employed contractors and workers provided by third-party agencies. The boundary of who counts as own workforce is broader than many organisations initially assume.

Who ESRS S1 Applies To

ESRS S1 applies to companies within the scope of CSRD where own workforce topics have been assessed as material through the double materiality assessment. In practice, own workforce impacts and risks are material for almost every company, because employment relationships inherently create actual or potential impacts on workers.

Materiality determines the specific disclosure requirements that apply, not whether the standard applies at all. Companies concluding that no aspect of ESRS S1 is material should expect that conclusion to face scrutiny during assurance, and they will need to disclose their reasoning.

The Main Disclosure Requirements

ESRS S1 includes disclosure requirements covering strategy, policies, actions, targets, and metrics. Some of the most demanding include:

• Description of the material impacts, risks, and opportunities relating to own workforce and their interaction with strategy and business model
• Policies related to own workforce, including how the company respects human rights
• Processes for engaging with own workforce and their representatives
• Channels for own workforce to raise concerns
• Actions and resources dedicated to addressing material impacts, risks, and opportunities
• Targets related to managing material impacts, risks, and opportunities
• A defined set of workforce characteristics, remuneration, and health and safety metrics

The metric requirements are where the operational challenge concentrates. They require quantitative data at a level of granularity that many organisations do not currently produce for internal reporting, let alone external disclosure.

The Quantitative Metrics: Where the Work Sits

A non-exhaustive summary of the quantitative metrics required under ESRS S1 includes:

• Workforce characteristics: total number of employees broken down by gender, country, contract type (permanent, temporary), and full-time or part-time status
• Non-employee workers: the number of non-employees in the company’s own workforce, with a description of the most common types
• Collective bargaining coverage and social dialogue: the percentage of employees covered by collective bargaining agreements
• Training and skills development: average training hours per employee, broken down by gender
• Health and safety: the percentage of workforce covered by the health and safety management system, number of fatalities, recordable work-related accidents and ill health, and days lost
• Remuneration: the gender pay gap and the ratio of annual total compensation for the highest-paid individual to the median annual total compensation for all other employees
• Diversity: gender distribution at top management level and age distribution across the workforce
• Adequate wages: confirmation that all employees are paid at least an adequate wage, benchmarked against applicable reference wages
• Incidents of discrimination and harassment: including complaints filed, fines, and remediation actions

Where Organisations Get Stuck

The most common operational challenges we see with ESRS S1:

1. Data Ownership Is Fragmented

Workforce data sits across HR systems, payroll platforms, health and safety records, learning management systems, and diversity monitoring processes. Bringing these together at the level of granularity ESRS S1 requires is a cross-functional exercise that no single team owns by default.

2. Non-Employees Are Not Systematically Tracked

Most HR systems are configured for employees. Contractors, agency workers, and self-employed individuals working for the company are often invisible to the core HR data model, yet ESRS S1 requires them to be counted, characterised, and in some cases assessed for exposure to material risks.

3. Definitions Do Not Match Internal Reporting

The ESRS definitions of full-time, temporary, and non-employee do not always match how the organisation classifies workers internally. A person recorded as a fixed-term employee for payroll purposes may need to be classified differently under ESRS S1. Building a mapping between internal categories and ESRS categories is a step organisations frequently overlook until data collection is well underway.

4. Pay Gap Calculations Are Not Straightforward

Calculating the gender pay gap and the CEO-to-median compensation ratio requires clean, consistent compensation data across the workforce, including bonuses and equity awards where applicable. Many organisations have this data but not in a form that produces a clean, disclosable figure without significant manual reconciliation.

5. Human Rights Due Diligence Documentation Is Thin

ESRS S1 assumes that the company has a functioning human rights due diligence process, aligned broadly with the UN Guiding Principles on Business and Human Rights. Where this process exists only informally, the documentation to support the required disclosures typically needs to be built.

What Assurance Providers Will Look For

Under CSRD’s limited assurance requirement, an assurance provider will focus on whether the data is complete, whether definitions have been applied consistently, and whether the narrative disclosures are supported by evidence.

For ESRS S1 specifically, this tends to mean:

• A clear mapping between the population reported and the underlying HR and payroll data
• Consistent application of contract type and worker type definitions
• Documented calculation methodology for pay gap, training hours, and health and safety metrics
• Evidence of the processes described in the narrative, such as engagement channels and grievance mechanisms
• A defensible position on the completeness of non-employee data

The single most common assurance finding on ESRS S1 is inconsistency between how the workforce is defined in the narrative and how it is counted in the metrics. A clear boundary definition, applied consistently, addresses most of the risk.

How Horizon ESG Supports ESRS S1 Reporting

Horizon ESG structures ESRS S1 data collection to reduce the cross-functional burden and improve the audit trail. Teams can:

• Configure ESRS S1 datapoints once and collect against the same structure each reporting cycle
• Import HR, payroll, and health and safety data through standard file formats
• Apply and version-control worker classification mappings, so that internal categories map cleanly to ESRS definitions
• Calculate and store metrics with the underlying data linked, supporting audit reproducibility
• Document policies, actions, and targets alongside the metrics they support
• Track incidents and grievances with structured evidence retention

The result is an ESRS S1 disclosure that is complete, consistent, and defensible under assurance, without requiring the HR and sustainability teams to rebuild the dataset each year.

A Practical Starting Point

If ESRS S1 has been deferred while the carbon workstream progresses, this is a good moment to begin the data mapping. The workforce data required is available in most organisations, but assembling it in the form the standard requires takes longer than the reporting timeline usually allows if left too late.

Book a free ESG software demo to see how Horizon ESG helps teams operationalise ESRS S1 alongside the environmental standards in a single, structured platform.