The CO₂ Performance Ladder in Belgium: what Flanders has required since 2025

What is the Ladder, and why does a Belgian tender mention it?

The CO₂ Performance Ladder is a Dutch certification scheme, run by the foundation SKAO, that public authorities use as an award criterion in procurement. It changes how your bid is scored. Treat it as a commercial instrument, since that is how contracting authorities use it. The mechanism keeps its Dutch name in Belgian tender documents: gunningvoordeel, tender advantage, usually granted as a fictieve korting or notional discount. If a tender grants 6 percent for your ambition level and you bid 10 million euro, your bid is evaluated as if it were 9.4 million. Win, and you are paid the full 10 million.

That is why the Ladder binds you commercially in Belgium even though no Belgian law obliges you to hold it. Roughly 8,000 organisations are certified worldwide, 75 percent of them SMEs, across more than 300 contracting authorities. If this is your first encounter with it, start with the CO₂ Performance Ladder explained.

What is the Flemish threshold?

Five million euro, for infrastructure works, since 1 January 2025.

The wording comes from the policy domain Mobiliteit en Openbare Werken (MOW, Mobility and Public Works), recorded by SKAO on 22 April 2024: "Wij zullen vanaf 1 januari 2025 de Ladder meenemen in bestekken voor infrawerken vanaf vijf miljoen euro en gradueel doortrekken." That is, from 1 January 2025 the Ladder goes into tender documents for infrastructure works from five million euro, and will be extended gradually. The threshold is a floor.

The Flemish road construction federation reported in December 2024 that the Ladder would be phased in from 2025 as an award criterion in investment and maintenance contracts, with AWV, De Vlaamse Waterweg and De Werkvennootschap preparing internal service orders.

Which Flemish authorities already use it?

The five million euro threshold was stated at policy domain level, where AWV and De Vlaamse Waterweg sit. No separate per agency threshold has been published, so the tender document remains the only thing that counts.

OVAM is the oldest Belgian example and the most underrated. Its announcement of 13 December 2021 already had the mechanism right: "Bedrijven die een hoog niveau halen, krijgen bij aanbestedingen een fictieve korting op hun inschrijvingsprijs." Companies reaching a high level get a notional discount on their bid price.

What has Wallonia decided, and what about Brussels?

Wallonia has committed. According to reporting on the government decision of 3 June 2026, SPW Mobilité et Infrastructures and SOFICO will include CO₂ criteria in their tender documents from 1 January 2027, with a transition phase during 2026. The rollout is staged: classes 6 to 8 in 2027, classes 4 and 5 added in 2028, and échelon 2 required for classes 4 to 7 in 2029. The volume is "environ 300 millions d'euros par an", covering "marchés de classe 4 à 8, soit à partir de 600.000 euros". The floor is 600,000 euro, the entry value of class 4.

Two sources conflict here, and that is worth stating. SKAO's own Belgium article, quoted above for the Flemish threshold, still reports positive signals in Wallonia but no decision. It is dated 22 April 2024, well before the government decision. The ministerial Walloon press release is more recent.

French language reporting uses échelon 1 and échelon 2. Échelon is the term SKAO uses in French for the steps (treden) of handbook 4.0, but Belgian French usage does not hold that line consistently, and the word alone does not prove which handbook version the tender document will cite. Ask for confirmation in the cahier spécial des charges. For what steps and levels mean, see the three steps of handbook 4.0.

Do you need a certificate to bid?

No. You declare an ambition level when you submit, and you demonstrate it within one year of award. SKAO's Belgian FAQ: "In beide gevallen moet de organisatie binnen een jaar na gunning en vervolgens jaarlijks, gedurende de looptijd van het project, aantonen dat het voldoet aan het gunningscriterium CO₂-Prestatieladder." The organisation must demonstrate, within one year of award and annually thereafter for the duration of the project, that it meets the Ladder award criterion.

Two things in that sentence get missed. The clock starts at award (gunning), and on a Belgian infrastructure contract award and start of works can be months apart. And it is an annual obligation for the life of the project. You demonstrate it either with a CO₂-bewust certificaat or with a projectverklaring, a project specific statement.

One legal boundary is firm. A certificate may not be a suitability or selection requirement: "De CO2-Prestatieladder is niet geschikt als geschiktheidseis of selectiecriterium." Requiring certification before a company may bid would be disproportionate and discriminatory towards small firms and foreign bidders. The Ladder belongs among the award criteria, inside the best price quality ratio assessment.

How much tender advantage does the Ladder give in Belgium?

The contracting authority decides. SKAO: "Welk percentage, bedrag of puntenaantal u als gunningsvoordeel kiest, bepaalt u zelf."

That table needs a warning. The Flemish percentages come from sector communication with no published decision behind them, and they use the old five level structure of handbook 3.1. The Walloon figures come from press reporting. The tender document is the only thing that counts in both cases.

One figure circulates in a misleading form. SKAO advises contracting authorities to set a contractual sanction larger than the advantage granted, for example the difference multiplied by 1.5. That is a recommendation. The Belgian FAQ imposes no penalty of its own, and what actually applies is written in your tender document. The full mechanism is in tender advantage with the CO₂ Performance Ladder.

Which Belgian bodies certify the CO₂ Performance Ladder?

Three of the fifteen accredited certification bodies on the Belgian list are Belgian: BCCA, COPRO and Vinçotte.

co2-prestatieladder.be publishes those fifteen bodies as one shared list, without splitting them by country, and states: "In Nederland is de Raad voor Accreditatie hier verantwoordelijk voor en in België Belac."

Since April 2024 BENOR is the coordinating partner in Belgium. SKAO says BENOR "zal ondernemingen en overheden begeleiden bij het certificeringsproces en het implementeren van de Ladder in bestekken", guiding companies and authorities through certification and through writing the Ladder into tender documents. The handbooks and the scheme stay with SKAO. The pilot phase was coordinated by CO₂logic.

The certificate is identical to the Dutch one and valid for three years, with annual surveillance audits (COPRO). The SKAO contribution and the certification body rates are the same as in the Netherlands, broken down in what the CO₂ Performance Ladder costs in 2026.

Does handbook 4.0 apply in Belgium too?

Yes, and the Belgian SKAO platform describes it correctly: "De vijf niveaus worden vervangen door drie treden, die meer ambitie vragen van organisaties." The five levels are replaced by three steps. Most pages ranking for this topic still describe five levels, which is wrong for 2026 and 2027 certification.

There is no separate Belgian handbook and no separate transition arrangement. The same dates apply:

That window is the reason to ask your certification body one question before you book an audit: is its 4.0 accreditation in place. The Belgian list does not publish that detail per body. Certification under 4.0 is visibly happening on SKAO's Belgian news overview, which carries Belgian organisations at step 1 and step 2 during 2025 and 2026.

Remember the asymmetry. A 4.0 certificate is valid in a tender asking for 3.1. The reverse does not hold, "omdat versie 4.0 veel verder gaat", because version 4.0 goes much further (SKAO FAQ). For the migration itself, see what you can reuse and what you have to rewrite.

Which emission factors apply in Belgium?

The Ladder prescribes country specific emission factor lists, which the GHG Protocol does not. For Belgium that is co2emissiefactoren.be, "een initiatief van CO2logic en EnergieID" with BENOR as partner, last revised in February 2025. For the Netherlands it is co2emissiefactoren.nl.

That trips up groups working on both sides of the border. The same litre of diesel does not automatically carry the same factor in a Belgian and a Dutch footprint. Fix the factor set per country and be able to evidence it. Two related rules: the Ladder defines green electricity as sun, wind, water or biomass produced in the same country where it is consumed, and carbon offsetting falls outside the Ladder's measurement scope, per Exergie.

What did the Belgian pilot phase of 2019 to 2023 show?

In 2019 the Flemish, Walloon and Brussels governments agreed to test the Ladder in large public contracts. SKAO's synthesis report of 11 March 2024 covers 09/2019 to 09/2023. The design was 25 public contracts, "10 en Flandre, 10 en Wallonie et 5 à Bruxelles". In the end 24 were registered across twelve contracting authorities, with only one launched in Brussels because of delays. OVAM launched nine further projects during the pilot that are not counted in that total.

Those three percentages come from a survey in summer 2023 of 33 of those 62 organisations. That is a small base, and it belongs next to the numbers. The contracting authorities in the pilot reported little extra time cost, enough compliant bids, and no price increases. SKAO reports an average reduction of 3.2 percent CO₂ per year among certified organisations against a national average of 1.5 percent, which is the most useful answer to the boardroom question of whether this achieves anything outside the tender.

The Belgian construction federation Embuild asks in its European memorandum for "een Europees wetgevingskader uitwerken voor de integratie van milieuclausules om het plaatsen van duurzame overheidsopdrachten mogelijk te maken", a European legislative framework for environmental clauses in public procurement, plus fiscal and financial incentives. Until that exists, the Ladder in Belgium is applied tender by tender.

Where does it actually go wrong?

Usually on organisational structure. A contractor group of any size runs two sets of books at once, statutory accounting on legal entities and operational accounting on business units, and the Ladder asks for a boundary that cuts across both. A sustainability lead summed it up: "The reason that this is so complicated is because you have two overlapping systems." See organisational boundaries across multiple entities. In Belgium the scope of your Ladder certificate is also a different entity list from the scope of your CSRD report, so a group level document sometimes has to be rewritten per certified entity.

Then there is vocabulary. Some auditors are, in a practitioner's words, "really allergic when you use step instead of level", or the reverse. In a country where the Flemish tender document still says niveaus and the Walloon one already says échelons, that is more than semantics. The general overview sits on our CO₂ Performance Ladder page.

How Palau handles this

Palau is a Belgian company and the CO₂ Performance Ladder is one of the supported frameworks. The Organisational structure module puts legal entities, business units and locations side by side and fixes the allocation key, so the scope of your certificate stays separate from the scope of your CSRD report. Vault keeps the evidence locked to the data point, with the source reference attached, so a split across three business units stays traceable for the auditor.

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