Sizewell C

Amentum is sole program and project management delivery partner for Sizewell C, a new nuclear power station that will strengthen the United Kingdom’s energy security.

The UK government gave the go ahead for the project in June 2025, saying that new nuclear was needed to deliver “a golden age of clean energy abundance”.

As well as mitigating risk through our program and project management role, Amentum will also support delivery teams from Sizewell C Ltd with digitally aligned project controls, engineering and technical services, and innovative infrastructure solutions for site management. The contract is creating hundreds of new jobs and will extend until the station begins generating electricity in the mid-2030s.

“Sizewell C’s always-on nuclear electricity will boost UK energy security at a time of volatile global gas prices, leading to lower and more predictable energy costs,” said Andy White, Senior Vice President of Amentum Energy & Environment International. “Our international program management experience and the learning from our work at Hinkley Point C will help to advance a project which is crucial for job creation and economic growth across the country. ”

Nigel Cann, Joint Managing Director of Sizewell C, said: “Amentum’s global program management capabilities and international nuclear new build experience will help us deliver the game-changing benefits and cost savings of replicating Hinkley Point C’s reactor design, while supporting our commitment to creating jobs and skills in the UK and maintaining the national capability essential for the nuclear renaissance.”

At Hinkley Point C, where Amentum is Delivery Partner for program, project and construction management, learning from experience between the construction of units 1 and 2 has produced estimated savings of more than 20%. Ensuring that these improvements are carried over to Sizewell C is a key priority for Amentum’s appointment as program manager.

Mark Whitney, President of Amentum Energy & Environment, said: “Our nuclear new build program management experience in the UK and elsewhere, together with our deep technical advisory capability, means that Amentum is well positioned at the forefront of the nuclear renaissance.”

Sizewell C Ltd is 76% owned by the UK Government, which has pledged investment totaling $23.9 billion (£17.8 billion). The station, on the East Suffolk coast in England, will have two 1.6 gigawatt EPR reactors capable of supplying electricity to six million homes while avoiding about nine million metric tons of carbon emissions each year. The project will support 70,000 jobs among more than 3,000 companies in the UK’s nuclear and construction supply chains. Sizewell C is the first nuclear power station in the UK that will be funded through a Regulated Asset Base model in which consumers are protected from bearing the risk of cost overruns through independent regulation, strict cost controls, and transparent oversight.