Is the CO2 Performance Ladder mandatory? No, unless the tender requires it
No. The CO2 Performance Ladder is not a law and not a mandatory standard. It is an instrument that contracting authorities can use in tenders. Whether you need the ladder is therefore determined by the contract you bid for, not by law. For how that advantage works, read tender advantage. For the available levels and steps, see levels and steps.
In practice the ladder is only mandatory if a client requires or rewards it. That is stated in the tender document, never in a law.
What does the handbook say?
Handbook 3.1 states that contracting authorities and organisations can use the ladder in tenders. A higher score can be rewarded with a notional discount on the bid price. The conditions for that are not in the handbook. Since handbook 3.0, those conditions and the related BPKV requirements are on the SKAO website and in the Handreiking Aanbesteden (Dutch procurement guidance). BPKV is the best-price-quality-ratio criterion: the way a contracting authority weighs quality alongside price.
That explains why the question “is it mandatory?” is so often misunderstood. The answer lies not in the standard, but in the contract you want to win.
What does the Handreiking Aanbesteden say?
The Handreiking Aanbesteden 3.1 from PIANOo (the Dutch centre of expertise on public procurement) is written for contracting authorities. Three points from the text are important for you:
- When you submit a bid, you choose yourself the ambition level you bid at. During performance you show that you meet that level.
- The ambition level you offer, including the lower levels, becomes part of the contract on award.
- Obtaining a CO2-conscious certificate is not a requirement under the BPKV criterion. It is one of the ways to demonstrate the ambition level. The other way is a project declaration, which applies only to that one project.
An example from the Handreiking: for a tender of €1 million, the contracting authority gives €30,000 (3 percent) notional discount for ambition level 3. This is an illustration from the Handreiking, not a fixed rate. Each contracting authority sets the scale itself.
Which handbook version counts now?
Handbook 3.1 is being phased out. SKAO published handbook 4.0 on 14 January 2025. According to the transition arrangement , 3.1 audits are still possible until 14 January 2027. A 3.1 certificate remains valid until the next annual audit, and at the latest until 14 January 2028.
For tenders, the following applies. A contracting authority that uses the 4.0 criterion is advised to accept only 4.0 certificates or 4.0 project declarations. A 3.1 certificate is therefore not enough there. A contracting authority that still uses the 3.1 criterion is advised to accept a 4.0 step 1 as level 3, and step 2 and 3 as level 5. Check in the tender document which version is required. The explanation per version is on levels and steps.
What is mandatory if you have a certificate?
If you have a certificate, obligations apply to keep it:
| Obligation | Where it is stated | What it means |
|---|---|---|
| Internal audit | Handbook 3.1, section 6.1.1.1 | At least once a year, an internal audit of the relevant requirements |
| Management review | Handbook 3.1, section 6.1.1.2 | Management reviews the CO2 management system at least once a year |
| Mandatory internet publication | Handbook 3.1, section 6.1.3 | From level 3 you publish the required information on your own website and on your page at SKAO |
| Annual contribution to SKAO | Handbook 3.1, section 6.1.4 | Without a paid contribution the certificate is not valid |
The internal audit is the obligation most often underestimated. Read the internal audit for the requirements and the audit process for the external assessment.
The publication obligation has a visible consequence. If you do not publish what you must, the assessor deducts 6 points. As a result, you do not reach the level. If you fall behind on payment, SKAO may remove your page from the website. From level 3 you then cannot obtain a positive ladder assessment.
When does the ladder become mandatory in practice?
Search the tender document for the passage about the CO2 Performance Ladder. There are roughly three situations:
| What the tender document requires | What you must do |
|---|---|
| No mention of the ladder | Nothing. Certification is voluntary and brings no advantage for this tender |
| Tender advantage per ambition level | You choose the ambition level you bid at and show during performance that you reach it, with a certificate or a project declaration |
| Minimum level or minimum step as a requirement | You must meet that level at that moment. Read exactly when and how you must prove it |
A minimum requirement makes the ladder the closest to mandatory. Pay attention to the moment of proof. Some forms ask for a declaration at submission, others only at the start of performance. That differs per tender.
Example: a road builder reads a tender
A fictional road builder, Van Dijk Infra, sees a municipal tender for redesigning a residential area. The document contains a tender advantage for ambition level 3 or higher. Van Dijk has no certificate.
The company does three things. It searches the document for “CO2” and reads how large the advantage is. It reads whether a project declaration is sufficient or whether a certificate is required. And it works out whether the advantage outweighs the costs. The calculation with a fictional discount is on tender advantage. Only if the document requires a certificate at submission is Van Dijk, without one, excluded straight away. If the document asks for an ambition level and proof during performance, Van Dijk can simply bid. The company arranges the proof with a certification body or with a project declaration.
Common misunderstandings
“The government always requires the ladder.” No. Each tender determines for itself whether the ladder counts, and at which level.
“My ISO 14001 certificate counts automatically.” No. An ISO certificate does not replace the ladder. Read ladder vs ISO 14001 for the difference.
“I must have a certificate to submit a bid.” Not always. Under the BPKV criterion, a certificate is one of the ways to prove the ambition level. Read the document.
“A 3.1 certificate will work everywhere.” No. A contracting authority that uses the 4.0 criterion is advised not to accept 3.1 certificates.
What does this mean for a small business?
A sole trader or small business does not need to obtain the ladder to exist. It only becomes relevant when you bid on a tender that takes the ladder into account. Then the question is whether the costs and effort outweigh the advantage on that contract. Someone who bids once a year calculates differently from someone who bids every month. The page for SMEs shows what a small organisation concretely needs to do.
Checklist for your bid
- Search the tender document for “CO2”, “CO2-Prestatieladder” and “tender advantage”.
- Note the level or step required, and whether it counts as a minimum or as points.
- Check which handbook version the document names, 3.1 or 4.0.
- Check when and how you must prove the ambition level: certificate, project declaration or both.
- Compare the costs and lead time with costs and timeline.
- Only start the step-by-step plan if the tender actually includes the ladder.
Does this apply to every sector?
Yes, the ladder is not tied to one sector. It appears most often in construction and infrastructure. See for construction and infrastructure and for SMEs. The FAQ answers more questions.