The economic crisis caused by the COVID-19 pandemic leads to a significant drop in incomes and tax payments. We consider express modeling of regional budget revenues depending on the depth of the crisis. The assessment is made for one of the Russian regions – the Chelyabinsk region. Purpose of the study. To build a mechanism based on available statistics for express estimation of the regional budget revenues. The comprehensive model for forecasting the region's enterprises' financial results, followed by a forecast of the regional budget revenues, was worked out. Materials and methods. Simulation models of macroeconomic indicators of the region's budget revenues are used in conjunction with enterprises' financial forecasting models. Big Data Analytics was applied to process financial statement data of the regional enterprises. Results. The model links the change in enterprises' financial results with the regional budget revenue dynamics. Based on scenario assumptions, the calculation of the change in financial results and tax bases of regional enterprises was made and the estimation of their contribution to the regional budget. The model allowed to form a forecast of revenues of the budget in the COVID-19 pandemic conditions. Conclusion. This approach combines meso- and microeconomics approaches and simulates the region's economic deve¬lopment as a multilevel system. The proposed model is universal and can be applied to consider the development of any Russian region.