The Office for Budget Responsibility (OBR), which monitors the UK government’s spending plans and performance, predicted borrowing of £15.1bn for September, less than the actual figure that came in.
The rise in borrowing in September brings the ONS figure for the first six months of the financial year to £79.6bn, compared with £73.0bn forecast by the OBR.
Despite outstripping official forecasts, the monthly figure was lower than expected by economists, who had collectively predicted borrowing of £17.5bn for September.
“While tax revenue increased, this was outweighed by increased spending, partly due to higher debt interest and public sector pay rises,” said Jessica Barnaby, deputy director for public sector finance at the ONS.