Britain's public sector net debt has exceeded £3 trillion for the first time, according to figures released by the Office for National Statistics (ONS) on Wednesday 21 October 2026.
Public sector net debt was provisionally estimated at £3,005.0 billion at the end of September, equivalent to 94.0% of gross domestic product (GDP). The cash total was £91.7 billion higher than a year earlier, although debt as a share of GDP was 0.7 percentage points lower.
September borrowing exceeds forecasts
The public sector borrowed £24.5 billion in September 2026, £1.8 billion more than in September 2025 and £1.9 billion above the Office for Budget Responsibility (OBR) forecast. It was the second-highest September borrowing figure on record in cash terms, behind September 2020.
Borrowing during the first six months of the 2026/27 financial year totalled £97.8 billion. That was £4.4 billion less than during the same period last year, but £6.0 billion higher than the OBR forecast.
Debt interest reaches £10.9 billion in one month
Central government debt interest payable was £10.9 billion in September, up £1.6 billion on the year and £2.0 billion above forecast. The ONS notes that movements in the Retail Prices Index affect interest payments on index-linked government debt.
Central government current spending was higher than a year earlier across public services, social benefits, debt interest and other costs. The ONS said spending increased more than government income, partly reflecting inflation.
Pressure ahead of the Budget
The figures arrive a week before the government's Budget, scheduled for 28 October. Higher-than-forecast borrowing and debt-interest costs add to the fiscal questions facing ministers, although the figures alone do not establish what tax or spending decisions the government will make.
Important context
The £3 trillion figure is a nominal cash milestone, not evidence that the debt burden relative to the size of the economy has reached a new record. The debt-to-GDP ratio of 94.0% was below the 94.7% recorded a year earlier, while remaining at levels last seen in the early 1960s.
ONS figures are provisional and may be revised. Public sector net debt is a stock of liabilities less liquid assets; monthly borrowing is a separate measure of the flow of new financing.