In this paper we present methods, data and algorithms for simulating budget system in the model of the Russian Federation spatial development. We show the place of this task in methodology of our research and give a brief overview of the background results. We determine revenues and expenditures of the budgets and funds on the basis of federal laws, Budget and Tax codes of the Russian Federation. For validation of the budget system algorithms in the model we conduct retrospective modeling for the federal budget and the budget of Belgorod region in 201
