The Covid-19 pandemic as well as the war in Ukraine represent the biggest hit to the Czech economy since the Great Recession. In the Czech Republic, several tax measures are being used to help economic entities overcome the current crisis and keep their businesses running. One of them is the tax instalment plan. This article aims to identify why the tax instalment plan could be an appropriate fiscal measure in times of economic crisis. The author presents a classical legal instrument in the tax area – the tax instalment plan – and analyses it from an innovative point of view rather than the usual perspective, that is, from the macroeconomic point of view. The article analyses the legal conditions for the use of this instrument in the Czech Republic, points out the difficulties of interpretation in practice and evaluates it in the context of the theoretical background of desirable fiscal crisis measures. The conclusions of the research confirm the hypothesis that this legal instrument is an effective and used tool for facilitating the sustainability of private and public finances in times of crisis. It combines the desirable aspects of both automatic stabilisers and discretionary measures.