CSRD compliance requirements explained: what Belgian companies must do now

That last part trips up a lot of the sustainability managers we talk to. They hear "Omnibus delay" and assume the pressure is off. It isn't. What's changed is the calendar, not the requirement to prove your sustainability claims with real, measurable action.

What does CSRD actually require from Belgian companies?

The Corporate Sustainability Reporting Directive, transposed into Belgian law, requires companies to include substantive sustainability information in their annual report, covering environmental, social, and governance topics. This isn't a marketing brochure attached to the annual report. It's an integral part of it, filed electronically with the Balance Sheet Office of the National Bank of Belgium.

Belgian legislation, as detailed by the FOD Economie, requires large companies, listed SMEs (excluding micro-companies), and certain non-EU companies operating through a Belgian subsidiary or branch to report on: their business model and strategy, the resilience of that model against sustainability risks and opportunities, their sustainability policies, any incentive schemes tied to sustainability performance for management and supervisory bodies, and measurable indicators tracking actual performance.

Parent companies of large groups face an additional layer: consolidated sustainability reporting across the whole group, not just the parent entity, according to the National Bank of Belgium's guidance on sustainability reporting.

We see this constantly in our work with sustainability managers preparing for their first CSRD cycle: the hardest part isn't understanding the legal text, it's finding indicators and initiatives concrete enough to survive an audit. A strategy slide about "commitment to biodiversity" doesn't hold up. A hectare of forest planted, monitored, and reported on does.

Who needs to comply, and when?

CSRD compliance in Belgium is phased by company category and financial year, not a single deadline for everyone. If you're not sure which wave applies to you, check your company's size classification and listing status first, because that determines your starting year.

The rollout works like this:

• Financial year 2024: the first reporting group, including certain listed companies.
• Financial year 2025: other large companies join the obligation.
• Financial year 2026: listed SMEs enter the scope.
• Financial year 2028: certain non-EU companies with relevant activity in the EU or Belgium.

This staggered structure means a mid-sized listed company and a large industrial group aren't playing by the same clock, even though both eventually report under the same standards. If your HR, sustainability, and communications teams haven't yet mapped which wave your company falls into, that's the first task, before anything else on this list.

Is CSRD still mandatory after the Omnibus delay?

Yes. The Omnibus adjustment shifts timing for certain company groups; it does not remove the underlying obligation to report sustainability information in the annual report. Belgian and European regulatory sources confirm the phased rollout continues, and the reporting duty remains in place for the relevant company categories.

Where the confusion comes from is understandable: "delay" sounds like "cancelled." It isn't. Treat Omnibus as a rescheduling of when you need to be audit-ready, not as permission to deprioritize the work. Companies that use the extra runway to build real evidence, rather than assuming the pressure disappeared, will be in a far stronger position when their wave arrives.

In our experience advising sustainability teams on materiality assessments, the companies that struggle most under CSRD aren't the ones reporting first. They're the ones who treated an earlier delay as a reason to wait, then scrambled when the deadline reappeared with the same evidentiary bar and less runway to build it.

What exactly do you need to prove, not just state?

CSRD demands evidence of how sustainability is embedded in strategy, governance, and performance, not a description of intentions. The National Bank of Belgium and FOD Economie are explicit that this information must be substantive: indicators, policies, and demonstrated resilience against sustainability risks, not a paragraph of aspirational language.

This is where most companies' existing ESG narratives fall apart under scrutiny. A statement like "we support local biodiversity" needs a number behind it: hectares restored, trees planted, species monitored, employees engaged. Auditors and stakeholders reading your annual report are looking for the same thing regulators are: can you show it, not just say it.

We've run this exact conversation dozens of times with CSR managers building out their materiality assessment. The gap is rarely ambition, it's proof. Companies know they want to act on biodiversity, carbon, or social impact; what they lack is a project concrete enough to generate the indicators their reporting requires.

How do you turn CSRD reporting into real, local action?

The most effective way to close the gap between CSRD's evidentiary requirements and your current reporting is to build tangible projects that generate their own data. A forest you've planted produces measurable outcomes: carbon sequestered, biodiversity restored, employees involved, hectares transformed. A strategy document does not.

This is exactly where our approach differs from a compliance consultancy that hands you a checklist and disappears. When we work with sustainability and HR teams together, the most reliable signal that a CSRD narrative will hold up isn't the quality of the writing, it's whether there's a physical, verifiable project behind the claim.

For companies looking for a fast, low-friction way to start generating that evidence, Start2Forest lets you invest in a collective corporate forest, planting trees annually on your company's behalf, starting from a minimum of five trees. Purchases of 100 trees or more include an employee planting event, which means your CSRD sustainability narrative comes with a real date, real photos, and real people from your own team standing in the forest they helped plant. That's the kind of concrete indicator that strengthens both your regulatory reporting and your internal engagement story at once.

For companies with underused outdoor space at HQ, converting it into a biodiverse micro-forest through our office forest program generates ongoing biodiversity and wellbeing data you can cite year after year in your sustainability report, not just once. And if your existing green space is more neglected than thriving, our nature restoration service rebuilds ecological value on land you already own, which is often the fastest route to a measurable indicator you can report this cycle.

What should sustainability and HR teams do before their reporting wave arrives?

Start building your evidence base now, regardless of which financial year your company enters CSRD scope. Map your reporting wave, identify which ESG themes your materiality assessment will need to substantiate, and choose at least one concrete project per theme that generates numbers, not adjectives.

Don't wait for the deadline to discover you have a strategy but no proof. The companies that treat the Omnibus delay as breathing room, not a reprieve, will walk into their audit year with a forest, a restored habitat, or a rooftop farm already producing the data their report needs, instead of scrambling to write around an empty page.

CSRD rewards companies that can show their sustainability work, not just describe it. Once you know that, your materiality assessment stops being a writing exercise and becomes a planning exercise: pick the projects first, let the report follow. The next concrete step is to request a project consultation and get a tailored plan for the forest, restoration, or biodiversity project that will back up your next sustainability report with something real on the ground.

Frequently asked questions

What are the CSRD requirements?

CSRD requires companies to include sustainability information in their annual report covering environmental, social, and governance topics: business model, strategy, resilience against sustainability risks, sustainability policies, governance incentive schemes, and measurable performance indicators. In Belgium, this applies to large companies, listed SMEs (excluding micro-companies), and certain non-EU companies with Belgian operations, filed with the National Bank of Belgium's Balance Sheet Office.

Is the CSRD mandatory?

Yes, CSRD is mandatory under Belgian law for large companies, listed SMEs, and qualifying non-EU companies, phased in by financial year starting 2024. The Omnibus delay adjusted timing for certain groups but did not remove the underlying legal obligation to report sustainability information in the annual report.

What is CSRD compliance?

CSRD compliance means including substantive, evidence-backed sustainability information directly in your company's annual report, not a separate marketing document. It requires demonstrating actual strategy, governance, and measurable outcomes across environmental, social, and governance topics, filed as part of the official annual reporting process with Belgian authorities.

What are the audit requirements for CSRD?

CSRD sustainability information must be substantive and verifiable, forming part of the audited annual report rather than a standalone claim. Companies need measurable indicators and documented policies that can withstand scrutiny, which is why projects generating concrete, trackable outcomes, like restored hectares or verified plantings, hold up better than narrative-only sustainability statements.

What is the CSRD Omnibus delay?

The Omnibus delay shifts the timing of CSRD reporting obligations for certain company categories without cancelling the requirement itself. Belgian regulatory sources confirm the phased rollout continues across financial years 2024 through 2028 depending on company type, so companies should use any additional time to strengthen their evidence base, not deprioritize compliance work.

Sources

• FOD Economie, 2024 — Belgian legal obligation for non-financial/sustainability reporting under CSRD.
• National Bank of Belgium, 2024 — Requirements for sustainability information reporting and filing with the Balance Sheet Office.