Grzegorz
Poniatowski

Grzegorz is a fiscal economist with a strong flair for quantitative problems. Over his 12-
year career, he has gained specialized knowledge and experience in estimating tax
compliance gaps, tax expenditures, and the revenue and distributional impacts of tax
reforms. Since 2012 he has been engaged in, and since 2015 led, the VAT Gap in the
EU study. This pivotal study annually estimates forgone VAT revenue due to non-
compliance and policy decisions. In addition to this, he has implemented and developed
alternative methodologies for estimating tax gaps in all major tax instruments, using
survey, audit, and national accounts data. Grzegorz possesses highly qualified expertise
in using econometric, general equilibrium, and simulation models to assess the impacts
of tax reforms.
Prior to joining Syntesia in 2024, Grzegorz has been an integral part of the Center for
Social and Economic Research (CASE) in Warsaw, where he most recently held the
positions of Director of Fiscal Policy Studies and Management Board Member. Over his
12 years with CASE, he led or contributed to over 60 research projects, evaluations, and
impact assessments for the EU, governmental, and international organizations.
Grzegorz’s consultancy work includes a tenure with the Eurasia Group, where he
advised on political and economic risks, provided policy outlooks, and conducted
thematic analyses on Polish economic policies. Since 2018, he has also worked on
various global assignments for the World Bank. Beyond the EU, his work has impacted
fiscal policies in countries such as Afghanistan, Indonesia, Georgia, Ghana, Kosovo,
Kyrgyz Republic, Moldova, Oman, Serbia, Solomon Islands, and Turkey. Furthermore,
collaborating with the IFC, he co-authored a study on investment determinants in
emerging markets.
Grzegorz obtained his PhD from the Department of Theoretical Economics at the
Warsaw School of Economics (Poland), where he has also served as Assistant
Professor teaching courses at the undergraduate, graduate and postgraduate levels.
Additionally, he holds an MA in Empirical and Theoretical Economics from the Paris
School of Economics (France) and a joint MA in Models and Methods of Quantitative
Economics from the University of Paris 1 Panthéon-Sorbonne (France) and the
Autonomous University of Barcelona (Spain). Grzegorz also completed an MA and a BA
in Quantitative Methods in Economics and Information Systems at the Warsaw School of
Economics.