The warning signs on the UK's public finances are flashing red, with a new Office for Budget Responsibility (OBR) report painting a stark picture of escalating debt over the next half-century. A stark 300% surge in public sector net debt by 2075, to £1.8 trillion from approximately £1.4 trillion today, puts future government borrowing capacity at severe risk.
The OBR's annual review of fiscal risks and sustainability warns that under current trajectories, public sector net debt is on an "unsustainable and ever-rising path". Key projections indicate PSND could swell to as much as 300% of Gross Domestic Product (GDP) by 2075, based on assumptions about productivity improvements. However, should these gains not materialise, the situation could be far worse, with PSND potentially reaching an astonishing 700% of GDP.
The OBR forecasts that revenue from net-zero affected taxes will tumble from 1.6% of GDP today to just 0.5% by 2075, placing increased pressure on the Exchequer to find alternative revenue streams. A significant factor contributing to this deteriorating prognosis is the impact of the UK's net-zero transition on the tax base.
The OBR identifies the state pension triple lock as the single biggest policy burden on public finances. This commitment ensures the state pension rises in line with inflation, wages, or 2.5% annually, and is projected to cause welfare spending to grow perpetually faster than the economy. The report illustrates that state pension spending as a share of GDP could almost double, from five per cent to nine per cent, over the next 50 years if the triple lock remains in place.
Underlying these fiscal challenges is the UK's rapidly ageing population. The OBR highlights that while historically driven by increased life expectancy, the primary factor over the coming decades will be a relative decline in the number of young people. This demographic shift presents a double challenge: an older population typically consumes more state resources, while fewer young people in the workforce mean fewer net-contributors to the tax system.