The Survey of Consumer Finances (SCF) is a triennial household survey with extensive demographic, income, and balance sheet information. The SCF is unique among public-use household surveys because it oversamples wealthy households and is thus suitable for studying wealth and income inequality across the entire population, but the survey does not collect detailed information about tax filing or tax liabilities. We develop a method for separating SCF households into tax units and creating the necessary inputs for estimating taxes using the NBER TAXSIM model. We validate our methods by benchmarking against published tax filings. Our methodology provides measures of after-tax incomes and effective tax rates for SCF households under current law and allows analysis of tax changes in ways that are not possible using administrative tax data alone.