In almost every third Russian company, the type of economic activity declared during registration does not coincide with the actual activity, a study of data from 352 thousand organizations showed. Non-conformities were identified in 28% of the enterprises covered in the first stage of the OKVED classification reform, and most of the non-conformities occur in trade, construction and real estate. It turned out that some companies receive the bulk of their income not from the declared business, but from renting properties or other operations. Changing industry classifications may result in loss of eligibility for government subsidies, preferential loans and increased insurance rates. The results of the audit show how significantly the official structure of the Russian economy can differ from the actual activity of individual enterprises.