The spread of the SARS-CoV-2 virus and the related restrictions on commercial transactions have an economic effect whose scale is difficult assess. At the same time, the need for activities intended to prevent and counter the epidemic results in a significant increase in public spending, which undoubtedly threatens the financial security of the state. For the above reasons, numerous rules that modify the principles of public finance management were introduced to the Polish legal system after the state of epidemic had been declared. The aim of the article is to present and analyse the amendments in the field of management of the general reserve and special purpose reserves that were introduced to the Polish legal system in order to ensure the proper execution of budgetary tasks during the pandemic. This aim is achieved through the presentation and analysis of the so-called Second Anti-Crisis Shield, i.e. the Act of 31 March 2020 amending the Act on Special Solutions Related to Preventing, Counteracting and Combating COVID-19, Other Infectious Diseases and the Resulting Crisis, as well as the provisions of the so-called Budget-Related Act for 2021, i.e. the Act of 19 November 2020 r. on Special Solutions to Implement the Budget Act for 2021. The implementation of the indicated research objective leads to conclusion that the introduced changes significantly broaden the scope of the executive’s decision-making competence in the implementation of the state budget, which may raise doubts in the light of the constitutional principle of exclusivity of the legislative authority in shaping state revenues and expenditures.