This guide provides an overview of the U.S. tax landscape for 2026, focusing on the implications of the One Big Beautiful Bill Act (OBBBA) and its impact on business tax provisions. It outlines key changes that businesses need to be aware of, including the revival of certain tax provisions that were previously phased out under the Tax Cuts and Jobs Act (TCJA). The document details specific provisions such as full expensing of research expenses, bonus depreciation, and modifications to business interest expense limitations. It also highlights the challenges faced by alternative energy companies and universities due to changes in tax credits and compliance requirements. The guide emphasizes the importance of understanding new rules regarding renewable energy incentives and the implications of IRS guidance on construction timelines for solar and wind projects. Additionally, it addresses the need for businesses to stay informed about ongoing IRS regulations and to work with advisors to navigate the evolving tax landscape effectively.