Abstract The article deals with the specificities of the definition of the notion of shadow economy, with core factors of its development and applied methods of measuring of its size are analyzed. An assessment of the current state, dynamics of the development and sectoral distribution of the shadow sector of the economy of EU countries is provided. Special attention is given to modern trends that positively or negatively influence the issue of fighting shadow economy in EU countries. Key methods of fighting shadow economy that are applied in EU countries are analyzed and the question of their effectiveness is considered.
Keywords Shadow economy, electronic transactions, economic actor, business model, gig economy, exchange market, economic sector, tax burden, social security contributions.