An independent contractor is an individual or legal entity that provides services to a client under a commercial services agreement rather than an employment contract. The contractor controls how, when, and where work is performed, supplies their own tools or methods, and typically takes on multiple clients. They are responsible for their own tax filings, social contributions, and professional insurance.
From a legal perspective, the classification test varies by jurisdiction. The US Internal Revenue Service applies a common-law test covering behavioural control, financial control, and the type of relationship. The European Court of Justice and the ILO use functional tests that look at economic dependence and subordination to determine whether a true independent relationship exists.
In the Netherlands, independent contractors are known as "zelfstandigen zonder personeel" (ZZP'ers). Since 2025, the Dutch tax authority (Belastingdienst) has actively enforced compliance under the Wet DBA, requiring engagements to genuinely reflect self-employment rather than disguised employment. Misclassification carries retroactive payroll tax liability for the engaging party.