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Published: 19/05/2026
The government’s latest update on HS2 has renewed concerns over the UK’s ability to deliver long-term infrastructure projects, after the scheme’s projected costs rose to as much as £102bn at 2025 prices.
HS2 may now not be operational until between 2036 and 2039, meaning the railway could take close to thirty years to deliver from initial approval to full operation.
The latest forecast is more than double the project’s original £32bn estimate at 2011 prices, equivalent to around £49bn at 2025 prices, while that earlier estimate also included the northern sections of the route that have since been cancelled.
David Crosthwaite, chief economist at BCIS, said the latest figures highlighted the growing challenge of managing inflation and long-term forecasting on major infrastructure schemes.
‘On projects spanning decades, regularly rebasing cost forecasts and stress-testing them against changing market conditions should be fundamental,’ he said.
‘One-third of the latest cost overrun has been attributed to inflation, with HS2 Ltd criticised for not updating inflation estimates frequently enough during the project life cycle.
‘Delays also increase exposure to rising labour, materials and financing costs, compounding the financial impact over time.’
Main construction work on HS2 only began in 2020, yet costs have already risen significantly despite the railway still being many years from completion.
Dr Crosthwaite also questioned whether the revised budget could realistically hold over the next fourteen years.
‘Given the pace of technological change, there is also uncertainty over whether a project conceived decades ago will still represent the best solution by the time it opens,’ he said.
Transport Secretary Heidi Alexander described the high-speed rail project as ‘a massively over-specced folly’ and ‘a symbol of this country’s decline’ as she outlined the latest position on the delayed programme.
The government has argued HS2 remains vital for improving rail capacity and connectivity, but the latest update is likely to intensify debate around how major infrastructure projects are scoped, governed and managed in the UK.
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