The arrangement was detailed in the British government’s Defence Nuclear Enterprise 2026 Annual Update to Parliament. Australia has committed £2.4 billion over ten years to expand Rolls-Royce infrastructure and share the cost of designing the new submarine.
SSN-AUKUS is a British-designed, nuclear-powered and conventionally armed attack submarine being developed with Australia and the United States. It will replace the Royal Navy’s Astute class and form the basis of Australia’s future nuclear-powered submarine fleet.
British boats will be constructed by BAE Systems at Barrow-in-Furness, while Australia will build its submarines at the Osborne Naval Shipyard in South Australia. Concentrating reactor production at Raynesway gives the British nuclear industry a long-term role across both national fleets.
The programme is progressing through its Detailed Design and Long Lead phase. Britain expects to decide how many SSN-AUKUS submarines it will order before the phase ends in 2028.
Contracts worth about £4 billion have already been placed for submarine development and the industrial infrastructure required to support production. Steel cutting for the first British SSN-AUKUS boat is planned for 2027, with entry into Royal Navy service targeted for the late 2030s.
The British government is investing about £6 billion over the Spending Review period to expand submarine construction capacity at Raynesway, Barrow and across the supply chain. The programme is intended to double the current production rate and establish a sustained output of one submarine every 18 months.
The expansion would allow Britain to build SSN-AUKUS attack submarines alongside Dreadnought-class ballistic-missile submarines. It would also make Derby a central production hub for the reactor technology underpinning the British and Australian SSN-AUKUS fleets.
