The Tax Cuts and Jobs Act of 2017 capped the federal tax deduction for state and local taxes (SALT) at $10,000 for single taxpayers and married couples filing jointly. That cap expires at the end of 2025 along with many of the other individual tax provisions. We propose permanently extending the cap. Based on an extrapolation of the estimates by the Joint Committee on Taxation (JCT) for the 2017 tax law, the extension of that provision would raise roughly $600 billion over ten years. The Brookings Institution and the Committee for a Responsible Federal Budget agree that the SALT deduction disproportionately benefits upper income taxpayers and have opposed repealing the cap.