The United States has pledged to become carbon neutral by 2050, meet sectoral objectives (e.g., for carbon free power, electric vehicles) and encourage greater mitigation among large emitting countries and of international transportation emissions. Fiscal policies at the national, sectoral, and international level could play a critical role in implementing these objectives, along with investment, regulatory, and technology policies. Fiscal instruments are cost-effective, can enhance political acceptability, and do not worsen, or could help alleviate, budgetary pressures. Domestically, a fiscal policy package could contain a mix of economy-wide carbon pricing and revenue-neutral feebates (i.e., tax-subsidy schemes) with the latter reinforcing mitigation in the transport, power, industrial, building, forestry, and agricultural sectors. Internationally, a carbon price floor among large emitters (with flexibility to implement equivalent measures) could effectively scale up global mitigation, while levies/feebates offer a practical approach for reducing maritime and aviation emissions.