To ask Her Majesty’s Government what is their estimate of the total cost of Trident renewal over the lifespan of the Successor-class submarines, including in-service costs and decommissioning.
6 June 2016
As stated in the 2015 Strategic Defence and Security Review, our latest cost estimate for manufacturing the four submarines of the Successor submarine programme is £31 billion, plus a contingency of £10 billion. This includes an assessment of the likely inflation over the lifetime of the programme and the risks appropriate for a project at this stage.
Once the new fleet of ballistic missile submarines comes into service, we expect that the in-service costs of the UK's nuclear deterrent, which include the costs of the Atomic Weapons Establishment, basing and disposals, will be similar to the current system, at around six per cent of the defence budget.
While we have no plans to replace the current Trident D5 missile, we are participating with our US partners in a programme to extend their lifespan to the 2060s. The estimated cost is around £250 million.