The Investing in State Energy Act of 2026 requires the federal government to speed up the distribution of funding and guidance for two major energy assistance programs: the Weatherization Assistance Program and the State Energy Program. Under the bill, federal agencies must release application guidance and publish funding allocations to states and other recipients within 60 days of receiving funding, and must distribute actual grant money to states within 30 days of receiving their energy conservation plans. The legislation affects state and local governments, Native American tribes, and energy efficiency and renewable energy initiatives that depend on these federal programs. The bill authorizes an additional $100 million annually for the State Energy Program for fiscal years 2027 through 2031, beyond the existing $500 million baseline. The faster timelines are intended to help states and communities more quickly implement high-impact energy efficiency and renewable energy projects.