Several OECD instruments highlight that fiscal and in-kind incentives provided to firms - such as tax exemptions, subsidies, or Special Economic Zones (SEZs) - should be periodically evaluated to ensure their relevance, effectiveness and cost-efficiency (OECD, 2015a; OECD, 2003). Such evaluations should not only consider the direct costs and effects associated with the support but also indirect effects on employment, competition and regional development, for example (Cizkowicz et al., There are currently 14 SEZs operating in Poland, whose functioning was prolonged until 2026.