Supreme Court Tariff Ruling: IEEPA Revenue and Potential Refunds
We project that reversing the IEEPA tariffs will generate up to $175 billion in refunds. Unless replaced by another source, future tariff revenue collections will fall by half.
Wanling (Lorraine) Luo is a Data Analyst at the PWBM. Her work focuses on business taxation, tariff modeling, and international tax, with an emphasis on translating fast-moving policy changes into scalable simulation tools and transparent, reusable analytical workflows.
At PWBM, she leads the ongoing development of the Tariff Revenue Simulator and is a primary contributor to PWBM’s tariff analysis and research output. On the business tax side, she is building the pass-through sector within the tax simulator and maintains core data pipelines that support the processing and analysis of business tax and financial data.
She holds an M.S. in Social Policy from the University of Pennsylvania and a B.A. in Economics from The Chinese University of Hong Kong, and is currently pursuing a Master of Computer and Information Technology at the University of Pennsylvania.
We project that reversing the IEEPA tariffs will generate up to $175 billion in refunds. Unless replaced by another source, future tariff revenue collections will fall by half.
We estimate that importers avoided 13.1 percent ($6.5 billion) of new tariffs by accelerating purchases and changing their purchasing patterns in response to the new tariff regime. Importers especially stockpiled pharmaceuticals and precious metals during 2025 Q1.
We analyze new data from the US Treasury to examine historical revenue effects of TCJA’s international corporate tax provisions. We also provide updated conventional estimates to assess the revenue impact of scheduled 2026 rate increases on foreign income of US corporations and assess several proposals that aim to further increase tax revenue.
After Ireland ended the Double Irish tax planning strategy in 2020, US firms with historical links to Ireland have shifted their intellectual property (IP) away from traditional tax havens to Ireland and the US to take advantage of tax incentives offered by both countries. This has coincided with a significant increase in Irish corporate tax revenue, particularly for less capital-intensive firms. Repatriation of foreign earnings to the United States has also increased, but fiscal benefits to the US have been offset by tax incentives passed under TCJA.