Question to the HM Treasury:

To ask the Chancellor of the Exchequer, what assessment his Department has made of the potential impact of extending official fiscal forecast horizons beyond five years on long-term capital investment planning.

The government updated the Charter for Budget Responsibility in 2024 to require that where capital investment, or other new policies, may have material impacts beyond the forecast horizon, the Office for Budget Responsibility (OBR) should, where appropriate and subject to receiving sufficient information from the Treasury to do so, analyse and report on these at the relevant forecast. The OBR estimates that the combined supply-side effects of policy announced across the Parliament will raise the level of GDP by over 0.6% after 10 years.

The government has taken a long-term approach to capital investment in the 10 Year Infrastructure Strategy, published in 2025. The Strategy set out the UK government’s long-term plan to provide greater certainty for infrastructure investment to support growth, resilience and high-quality public services.