Steel will be cut on the first British SSN-AUKUS submarine in 2027 under current plans, marking the start of production on the class that will replace the Astute boats, according to the Defence Nuclear Enterprise annual update to Parliament.
The programme has already placed contracts worth around £4 billion, supporting development of the capability and the industrial infrastructure needed to deliver the next generation of attack submarines.
The update states that the programme “remains focused on delivering the first Royal Navy SSN-AUKUS submarine into service in the late 2030s”.
SSN-AUKUS is being developed through the partnership with the United States and Australia, and is based on a British design. It is currently progressing through the Detailed Design and Long Lead phase, with decisions on the total number of submarines to be procured expected before that phase ends in 2028. Construction of the British boats will take place at BAE Systems’ Barrow shipyard, while Australia will build its own at Osborne Naval Shipyard in South Australia. The next generation of nuclear reactors for all SSN-AUKUS submarines, including Australia’s, will be built at Rolls-Royce Submarines’ Raynesway site near Derby.
Britain will also supply key components to the Australian programme while Australia develops its industrial capacity, which the update describes as creating a resilient supply chain across both nations. Australia has invested £2.4 billion over ten years to boost Rolls-Royce infrastructure and to share costs on the submarine design, an investment the update presents as recognition of the importance of British industry to developing the capability.
The Geelong Treaty signed between Britain and Australia in July 2025 further strengthened the partnership, and the update describes it as an agreement for the next fifty years of bilateral defence cooperation under AUKUS Pillar I, enabling comprehensive cooperation on the design, build, operations, sustainment and disposal of the submarines. That was followed in March 2026 by the visit of the Astute-class HMS Anson to HMAS Stirling in Perth for a submarine maintenance period, which the update describes as a major milestone in delivering the Pillar 1 Optimal Pathway.
Preparing to build the class requires work on the yards as well as the design. In early 2026 the concept design was completed for SMITE2, a new submarine propulsion testing facility at Barrow, which the update says will deliver modernised and expanded engine and machinery assessment essential to sustaining an accelerated production tempo. At Raynesway, work includes the recent groundbreaking of a major Primary Components and Operations Facility alongside improved site access and advanced prototyping facilities.
The wider objective set out in the update is a drumbeat of one submarine every eighteen months, supported by £6 billion committed under the Defence Investment Plan for infrastructure at Barrow and Raynesway. A Submarine Production Alliance is being established to bring BAE Systems, Rolls-Royce Submarines and Babcock together with the Ministry of Defence to deliver future programmes.
Well we shouldn’t have any caps if this takes around 10 years.
First Astute would retire in 2035 if it’s ran for 25 years. However due to the fact they haven’t been used nearly as much as they were expecting I’m sure it won’t be too hard to push its life an extra years or two. Then move the crew to train up on the new subs before they fully get commissioned
Up to 12 still it seems. Give us 10 and I’d be thrilled
Any increase will be welcomed, even if it were nine that would make maintaining three at sea much easier a be a huge leap.
May be a perfectly good reason for this but why can’t they take a few of the Astute boats back into the build hall and fix them as we seem a little short on dry dock space at the minute.
It’d be really hard to get the boats back into Barrow, once they leave.
the build hall is full to the gunnels with two Giant SSBN’s at the moment and Astute 7. Nothing needs fixed on the Astutes its primarily certification issues.
This was known all the way back when the DIP came out.
Good to get them started. This means we’re probably getting at least one. Twelve would be great, but I think ten would be fine in terms of industrial management and more than good enough for the Northern Fleet.
it will be the one upside of the past five years and the abysmal maintenance situation that we find ourselves in that both Astute SSN and T45 in that both can have their service lives significantly extended. No reason HMS Astute can’t go to 2040 or even later.
The real naval threat the west faces is in the 2030’s and 2040’s as the Russian working navy remains small and China is only just getting to grips with SSN production.
The USN needs to seriously consider buying SSN AUKUS as well, it’s their only hope in growing their submarine fleet. The UK could spin up another submarine production facility at Cammel Laird with the kind of cash the US has available, and Derby could always build more reactors. They are gearing up to knock out two giant 400mw SMR each year so pumping out an extra PWR 3 every other year for a US boat is very doable.