This paper derives standardized measures of labor and capital income that account for the different reporting requirements and incentives faced by different forms of organization. This facilitates estimating how much capital income is subject to employment taxes and how much labor income escapes employment taxes (specifically, those levied under the Federal Insurance Contribution Act (FICA) and Self–Employment Contributions Act (SECA)). The paper also shows an additional reason why economic incidence of taxes is different from statutory incidence, namely that different entity types are taxed on their labor and capital income in different ways, have different reporting requirements and, therefore, have differing incentives for taxpayers to mischaracterize their income with the intention of reducing liability. Ultimately, tax filing requirements cause some capital income of sole proprietors and general partners to be subject to employment taxes as if it were labor income. Furthermore, taxpayer behavior causes some labor income of limited partners and shareholders of S and privately held C corporations to escape employment taxes.