PolicyEngine US

PolicyEngine US is an open-source Python library that provides a comprehensive microsimulation model of the United States tax and benefit system. Built upon the PolicyEngine Core framework (a fork of OpenFisca), it accurately models federal individual income taxes, major federal benefit programs, and state income taxes for all 50 states and D.C. The library enables researchers and policymakers to estimate household-level tax liabilities and benefit eligibility, and to simulate the distributional impacts and budgetary effects of proposed policy reforms. It is actively maintained with continuous updates driven by changes in tax and benefit legislation.