In the article, authors describe an issue of evaluating the effectiveness of the consolidated groups of taxpayers (CGT). In the context of the work the criteria for the evaluation of the tax system by various authors were described and criteria for evaluating the effectiveness of CGT were identified. The authors proposed the methodology of evaluation activities of CGT on the basis of identified criteria. The results of the evaluation can be used to make changes in Russian legislation, due to which additional finance for the development of the country can be attracted.