Purpose – The aim of the paper is to assess changes in the functioning of open pension funds (OFE-s) in the context of Poland’s fiscal situation. These changes are beneficial from the point of view of the current condition of the public finance sector, however in the longer term they may have a negative impact on Poland’s fiscal situation. Research method – The authors analysed and processed data and information available from Eurostat, the Central Statistical Office, publications from the Ministry of Finance, the stooq.pl portal listing quotes on the financial market and publications in which the authors estimated hidden debt in Poland. Based on the analysis undertaken, conclusions relating to the studied problem were formulated. Results – The changes initiated in 2011 and consisting in limiting the significance of the capital pillar of the social security system in Poland (OFE-s), and subsequently planned in 2020, the final liquidation of open pension funds has a positive effect on the current condition of the public finance sector in Poland limiting the borrowing needs of the state, the deficit and registered public debt. The changes weaken Poland’s fiscal position as they contribute to a significant increase in hidden debt recorded on individual accounts and sub-accounts at the Social Insurance Institution. Originality /value – It was proved that in the years 2013-2019 the indexation rate (measured by the geometric mean) of funds on pension sub-accounts at the Social Insurance Institution was 36.7% higher than the profitability of 10-year treasury bonds, thus generating additional hidden debt. The analysis also indicated the possible negative long-term consequences for Poland’s fiscal situation resulting from the final liquidation of open pension funds.