Knowledge base › The basics of public procurement
What the three main rulebooks say and which rules protect you as a bidder against disproportionate requirements.
Checked on 15-09-2026
The Dutch Public Procurement Act 2012 (Aanbestedingswet 2012) is the foundation. Part 1 contains principles that also apply below the European threshold. The core is in articles 1.10, 1.13 and 1.16, for European, national and multiple private procedures respectively: a contracting authority sets only requirements, conditions and criteria that are in reasonable proportion to the contract. The Act mentions, among other things, the combining of contracts, suitability requirements, time limits, award criteria and contract terms.
How this works in practice is set out in the Proportionality Guide (Gids Proportionaliteit), a guideline designated by law. The version in force is the third revision of 1 January 2022. The Guide applies to European, national and multiple private procedures. The principle is comply or explain: if an authority departs from a rule, it states its reasons in the tender documents (article 1.10, paragraph 4).
Some rules that affect you directly as a bidder: the authority asks for at most one reference per core competency, and a reference project need not exceed 60% of the estimated contract value (3.5 G). A consortium is not given heavier requirements than a single bidder (3.5 H). Security is at most 5% of the contract value (3.5 D). Unlimited liability is not required (3.9 D). The Act itself provides that a turnover requirement is no higher than three times the estimated value of the contract (article 2.90).
For works below the European threshold, the Works Procurement Regulations 2016 (ARW 2016) apply. They are mandatory for contracting authorities through the Procurement Decree, again on a comply-or-explain basis. Authorities may use them voluntarily for supplies, services and European tenders.
What this means for you: read the requirements in tender guidelines against these rules. If you find a requirement too heavy, raise it in the question round and refer to the rule. The Guide expects bidders to raise objections as early as possible after publication; waiting until after the award weakens your position.
These articles explain how public tendering works; they are not legal advice. If you are unsure about a specific tender, ask your question through the clarification round or consult a lawyer.
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