Sustainability report: what it includes and which rules apply in 2026

A sustainability report is the document a company uses to communicate its environmental, social and governance (ESG) performance over a financial year: what impacts it has, how it manages them and what targets it sets. It is the standardised way of accounting for everything that does not appear in traditional financial statements but affects the company's value and reputation.

In 2026 the regulatory framework around these reports has changed significantly because of the Omnibus package.

What a sustainability report is

The sustainability report sets out, in a structured and verifiable way, an organisation's non-financial information. Its purpose is twofold: transparency towards stakeholders (investors, customers, employees, authorities) and management, because measuring and publishing forces you to set targets and improve.

Unlike marketing communication, a good report rests on traceable data, follows a recognised framework and, where the law requires it, undergoes external assurance. That is the difference between reporting and greenwashing.

What a sustainability report includes

Although the specific content depends on the applicable framework and the company's size, almost all reports are organised around the three ESG pillars:

• Environmental (E): carbon footprint and greenhouse gas emissions by scope, energy and water use, waste generation and management, circular economy and biodiversity.
• Social (S): employment and working conditions, health and safety, equality and diversity, training, and relations with communities and the value chain.
• Governance (G): governance structure, ethics and anti-corruption, risk management and sustainability policies.

A cross-cutting element is the double materiality analysis: identifying which matters are relevant both for their impact on the environment and for their financial effect on the company. It is the filter that decides what gets reported and in how much depth.

Which rules apply in 2026

This is the point that changes most. In 2026, three levels coexist.

CSRD and ESRS after the Omnibus

The CSRD is the European directive that requires sustainability reporting under the European Sustainability Reporting Standards (ESRS). The Omnibus package, whose directive was published in the Official Journal of the EU on 26 February 2026, reshaped its scope and timeline. In short:

• The mandatory scope rises to companies with more than 1,000 employees and net turnover above 450 million euros.
• The changes apply to financial years beginning on or after 1 January 2027 (with the first reports under the new perimeter in 2028).
• The ESRS are simplified to reduce the number of data points to report.

The EINF in Spain

Until Spain completes its transposition of the CSRD (planned through the future Sustainability Reporting Law, still in progress), companies outside the CSRD scope keep publishing their Non-Financial Information Statement (EINF) under Law 11/2018. In practice, the EINF is the mandatory sustainability report for large companies in Spain during this transition. You can see who it binds and what it includes in the guide on the EINF: who is required and what it includes.

Voluntary frameworks: GRI and ESRS

Many companies report voluntarily, whether because they fall outside the mandatory scope or because their customers and investors ask for it. The reference frameworks are the GRI Standards from the Global Reporting Initiative, the most widespread internationally, and the ESRS themselves used voluntarily or in simplified form.

Report, memoria and EINF: the difference

The terms get mixed up, but they are worth ordering:

In practice, "report" and "memoria" are often used interchangeably; the EINF is a specific, mandatory format within that universe.

How to prepare a sustainability report

Whatever the framework, the process follows a similar sequence:

1. Define the framework and scope: decide whether you report under ESRS, GRI or EINF and which entities and activities you include.
2. Run the double materiality analysis: identify the matters relevant by impact and by financial risk. This step orders everything else.
3. Collect and measure the data: the environmental block almost always starts from the carbon footprint; gather water, waste, workforce and governance data too.
4. Write with comparable indicators: rely on recognised KPIs so the information is traceable and comparable year on year.
5. Assure and publish: where the law requires it, submit the report to external assurance before publishing.

If you will report under the European framework, the guide to implementing the ESRS in your company step by step will help you structure the project.

Frequently asked questions

Is a sustainability report the same as an EINF?

Not exactly. "Sustainability report" is the general term for the document reporting ESG performance. The EINF is a specific, mandatory format regulated by Law 11/2018 in Spain. Every EINF is a sustainability report, but not every report is an EINF.

Which rules apply to my report in 2026?

It depends on your size and country. In the EU, the CSRD with the ESRS binds large companies (over 1,000 employees and 450 million turnover) for financial years beginning from 2027. In Spain, while the CSRD is being transposed, many companies keep to the EINF under Law 11/2018. Others can report voluntarily under GRI or ESRS.

Where do I start if I have never done a report?

By measuring. The environmental block, and specifically the carbon footprint, is usually the most solid starting point, because it structures the data and gives comparable results on which to build the rest of the report.

Prepare your sustainability report with Manglai

The basis of any sustainability report is reliable environmental data. With Manglai your company measures its carbon footprint from its bills and real data, and generates the ESG information it needs to report under ESRS, EINF or voluntary frameworks like GRI.