The article considers the decrease in the reliability of expenditures’ budgeting in Germany that has occurred in recent years. The author used the data on the formation and execution of a five-year financial plan for 2017‒2021. The comparison of this plan with its execution was carried out in four profiles: total expenses by functional classification, total expenses by economic classification, current expenses by functional classification, capital expenses by functional classification. Using the same methodology, the author previously compared plans for 2002‒2006, 2007‒2011, 2012‒2016 with their execution. The results of the calculations made it possible to identify areas with increased and decreased accuracy of budget planning, key areas of significant overspending of budget funds in 2020‒2021 and reasons for the deviations. In addition, the author analysed the most important consequence of the deterioration in the accuracy of budget projections – the return to the deficit and net borrowings of the federal budget. The dynamics of expenses, net borrowings and the ratio of net borrowing to expenses in 2002‒2021 and a plan for these parameters for 2022‒2026 are presented. Based on the data reviewed, a conclusion was drawn about the critical importance of 2023 for restoring the lost reliability of federal spending planning.