The UK Office for National Statistics (ONS), in its public-finance bulletin of 22 September, reported public-sector net borrowing of £18.3 billion in August 2026. That was £2.9 billion, or 19%, above August 2025 and £3.5 billion higher than the Office for Budget Responsibility (OBR) forecast. The ONS attributed the increase to spending growth outpacing the rise in receipts. Borrowing measures the gap between public-sector spending and income; a positive figure represents a deficit. The August amount is not adjusted for inflation and was the second-highest August figure in the ONS record, behind 2020.

Net borrowing for the financial year to August, covering April through August, totalled £77.3 billion. It was £2.2 billion, or 2.7%, below the same period a year earlier, but £8.1 billion above the OBR forecast. The five-month total equalled 2.5% of GDP, the tenth-lowest April-to-August share since comparable monthly records began in 1993. The ONS notes that year-to-date comparisons offer a more reliable view of underlying trends because monthly figures can be more exposed to short-term forecast volatility. Self-assessed income-tax receipts for July and August combined were £18.6 billion, £1.9 billion more than a year before.

Public-sector net debt was provisionally estimated at £2,985.5 billion at the end of August, £78.5 billion more than a year earlier but equivalent to 93.8% of GDP, down 1.3 percentage points year on year. Net financial liabilities, a broader balance-sheet measure, stood at £2,620.4 billion, or 82.3% of GDP. These debt-stock measures differ from borrowing, which is a flow over a period. The ONS said its September release incorporated annual data updates and methodological improvements and that early fiscal estimates may be replaced as more information becomes available. The monthly and financial-year figures are official estimates; the gap against the OBR forecast alone does not establish future budget policy or the outcome of a new decision.