The principle of subsidiarity in the activities of the institutions of the European Union

This article examines the practical application of the principle of subsidiarity in the work of the main EU institutions – an issue of particular importance in the context of Ukraine’s European integration trajectory and the continued expansion of the Union’s policy scope. The point of departure is the gap between the Treaty formulation in Article 5(3) of the Treaty on European Union (hereinafter “TEU”) and day-to-day legislative practice. In particular, it is necessary to substantiate the question “why at EU level?”, to determine the appropriate intensity of intervention, and to clarify the link with impact assessment. The article proposes an institutional and procedural framework that turns subsidiarity into a repeatable, evidence-based standard. It demonstrates that, within the European Commission, key instruments include the Better Regulation Guidelines and their annexes, which systematically require: level-of-action tests; analysis of alternatives between national and European levels; selection of the appropriate instrument (coordination, minimum harmonisation, or full harmonisation); assessment of regulatory burden with a dedicated focus on SMEs; consideration of the territorial dimension; and a monitoring plan. External scrutiny is provided by the Regulatory Scrutiny Board. In the European Parliament, subsidiarity is supported by procedural filters in committees (Rule 43 and the role of the JURI Committee), analytical input from the European Parliamentary Research Service (EPRS) (initial assessments of impact assessments, ex ante analysis for amendments, and ex post evaluations), and the “European added value” strand, which quantitatively compares options and estimates the “cost of non-Europe”. In the Council of the EU, subsidiarity checks are conducted in preparatory bodies and in Coreper, while the Legal Service safeguards adequate reasoning and drafting quality; transparency of “legislative deliberations” and trilogues translates subsidiarity findings into recitals and operative provisions. The European Council sets political thresholds through strategic guidance and transitional mechanisms without substituting for the legislator. The Court of Justice of the European Union applies a restrained yet structured form of review; leading judgments delineate the criteria for an appropriate choice of level. The Committee of the Regions complements the system through its right to bring actions in cases where consultation is mandatory, while the European Economic and Social Committee (EESC) provides socio-economic expertise. For Ukraine, the article formulates practical guidance: a “subsidiarity chain” from impact assessmentto review indicators; a checklist for explanatory memoranda and parliamentary assessments; and the integration of territorial and SME dimensions. The result is a standardisation of evidentiary requirements, a reduction of unnecessary regulatory burden, and strengthened legitimacy of decision-making.