HS2 Phase 2b is estimated as delivering high value for money, with a Benefit-Cost Ratio including Wider Economic Impacts (WEIs) of 2.6 and a BCR excluding WEIs of 2.1. This analysis was presented in the Phase 2 Economic Case in 2017.
The business case for Phase 2b assumes that up to 18 trains per hour will run on the HS2 core network at speeds of up to 225mph (360km/h). HS2 Ltd is working to the scope of the project as set out by Government. If any changes were made to these requirements then there would be an assessment of the potential impact on the business case and this work would be published.