UK Government Debt Interest Could Consume Nearly Half of Future Tax Revenue

Government debt repayment costs could consume up to 47 per cent of total UK tax revenues by 2075 under worst-case economic scenarios, according to long-term fiscal modelling published by the Institute for Public Policy Research (IPPR). The projections highlight severe structural pressures facing younger generations and taxpayers across coming fiscal quarters.

Debt interest payments for the current financial year are projected to total £110bn, matching the scale of the entire education budget and nearly doubling national defence spending. According to Office for Budget Responsibility (OBR) data, these servicing costs currently absorb just over eight per cent of total public expenditure, which translates to roughly 3.6 per cent of gross domestic product.

Yields on UK gilts have climbed steadily amid ongoing market anxiety regarding loose fiscal strategies and persistent challenges in curbing state borrowing through tax adjustments or expenditure caps.

Long-Term Fiscal Strains on Generation Z and Generation Beta

Under the IPPR’s most-likely economic scenario, debt interest payments will claim 21.3 per cent of total government revenue in the decades ahead. Economists warn that without systemic structural reform, the youngest members of Generation Z and Generation Beta—born between 2025 and 2039—will bear disproportionate economic disadvantages stemming from escalating national liabilities.

The IPPR findings rely on comprehensive data from the OBR. OBR leadership has repeatedly emphasized that mandatory health and pensioner spending will inevitably expand as a share of GDP. At the same time, productivity growth faces compounding downward risks from climate-related economic shocks.

Calls for Reform to the UK Fiscal Framework

While economic analysts urge Chancellor John Healey to maintain existing fiscal rules through at least 2030, policy experts advocate for a redesigned fiscal framework. This revised architecture would explicitly distinguish borrowing earmarked for long-term, productivity-enhancing infrastructure investments from debt that merely expands short-term liabilities.

The current fiscal framework, established by former Chancellor Rachel Reeves, requires tax receipts to match or exceed day-to-day departmental spending by the third year of a rolling forecast. A second rule dictates that public sector net financial liabilities must decline as a share of GDP over the same window.

William Ellis, senior economist at the IPPR and co-author of the research report, argued that Whitehall should only reconsider these core rules from a position of economic strength once targets are consistently met. A reformed system should deploy a dedicated financial dashboard tracking short, medium, and long-term horizons, while making the trade-offs of public investments transparent.

These policy shifts mirror arguments raised by high-ranking officials including Louise Haigh, who criticized narrow short-term forecasting models. Under the IPPR proposals, fiscal sustainability would feature a strict backstop triggered if debt-servicing ratios exceed a critical 15 per cent threshold of total government expenditure.