The aim of the paper is to analyse the irregular budget receipts, their behaviour and impact on budget deficits in Kosovo. Since its independence, Kosovo has been engaging in large infrastructure projects based mainly on initially high cash balances and overestimation of revenue capacity, in particular of irregular receipts. This led to the creation of future liabilities and budget deficits, which had to be financed by public debt. Further, the politically motivated increase of wage and salary bill and social transfers increased the burden on budget deficit already caused by infrastructure projects. Thus, budget deficits became the lasting feature of Kosovo economy. All this was supported by a lack of legal infrastructure or fiscal rules for several years. There is extensive literature on the causes of budget deficit, its definition and measurement. The literature review method is adopted in the present study, and research is refined by including selected papers that contain empirical and theoretical studies on budget deficit. Therefore, special-purpose deficit, the so-called “regular” budget deficit, which considers only regular receipts and outlays, has been defined and measured in the present study. This analysis leads to the conclusion that irregular receipts used by the government to engage in large infrastructure projects and/or the politically motivated increase of wage and salary bill and social transfers lead to a budget deficit that has to be financed through public debt. This is a case study of Kosovo and research has been carried out using primary data drawn from Kosovo budget annual financial reports. The implications of the paper may be of high importance for policymakers as well as for academic issues. This is a unique approach to the issues of Kosovo budget deficit and irregular receipts.