The United States operated 96 commercial nuclear reactors at 57 power plants across 28 states as of March 2026, according to the U.S. Energy Information Administration. Combined, those reactors carry a net summer electricity generation capacity of about 98,441 megawatts, most of it concentrated east of the Mississippi River.

Illinois hosts more nuclear capacity than any other state, with 11 reactors at six plants totaling roughly 11,592 megawatts at the end of 2025. Georgia is home to the largest single nuclear plant in the country, the Alvin W. Vogtle Electric Generating Plant near Waynesboro, where four reactors provide a combined 4,530 megawatts of summer capacity. The newest reactor to enter commercial service nationwide, Vogtle Unit 4, began operating in April 2024.

Most U.S. nuclear plants host more than one reactor. Of the 57 operating plants, 22 have a single reactor, 31 have two, three have three reactors, and one, the Vogtle Electric Generating Plant in Georgia, has four. EIA data show the average age of the operating fleet at about 44 years, with the oldest reactor, Nine Mile Point Unit 1 in New York, dating to 1969.

Looking ahead, EIA's Annual Energy Outlook 2026 Counterfactual Baseline case projects total nuclear generating capacity will grow modestly through 2050, even as nuclear's share of total U.S. electricity generation is projected to decline from 17 percent in 2025 to between 12 and 15 percent, as electricity demand from other sources grows faster than new nuclear capacity comes online.

Source: U.S. Energy Information Administration - https://www.eia.gov/energyexplained/nuclear/us-nuclear-industry.php