What is Construction Permit?

An NRC authorization under 10 CFR Part 50 that allows the holder to begin constructing a nuclear power plant at a specific site, subject to subsequent application for an operating license before fuel loading.

What category does Construction Permit belong to?

Construction Permit is a regulatory concept in nuclear energy and SMR technology.

Construction Permit — Nuclear & SMR Glossary

A Construction Permit (CP) is the first of two authorizations required under the NRC's traditional Part 50 licensing pathway, granting approval to physically construct a nuclear power plant at a specific approved site. The CP process requires the applicant to submit a Preliminary Safety Analysis Report (PSAR), an Environmental Report, and demonstrate that the proposed plant can be built and operated without undue risk to public health and safety. Notably, a CP does not authorize fuel loading or reactor operation; a separate Operating License (OL) application must be submitted and approved before the plant can begin nuclear operations. Despite being the older licensing approach, Part 50 CPs have emerged as the preferred pathway for several advanced reactor demonstration projects.

The construction permit has become the critical near-term regulatory milestone for the advanced reactor industry. Kairos Power's Hermes low-power demonstration reactor in Oak Ridge, Tennessee received the first NRC construction permit for a non-light-water advanced reactor in December 2023, marking a watershed moment for the industry. TerraPower's Natrium plant in Kemmerer, Wyoming subsequently received its construction permit in 2025, after the NRC completed its final safety evaluation in December 2025. These two permits represent the furthest any advanced reactor designs have progressed through U.S. regulatory approval. Holtec International submitted a partial CP application for its twin SMR-300 units at the Palisades site in December 2025, which was accepted for docketing by the NRC in February 2026.

X-energy's CP application for four Xe-100 modules at Dow's Seadrift, Texas manufacturing facility was accepted by the NRC in May 2025, with construction planned to begin in 2026. In Canada, the analogous milestone is the License to Construct issued by the CNSC, which OPG received in April 2025 for the BWRX-300 at Darlington, Ontario, leading to construction commencement in May 2025. The choice between a Part 50 CP and a Part 52 Combined License involves strategic trade-offs: CPs allow construction to begin before the operating license review is complete, potentially saving time for first-of-a-kind projects where the operating license can be pursued in parallel, while COLs provide greater upfront regulatory certainty by authorizing both construction and operation in a single proceeding.