The Office for Budget Responsibility has said its leadership must take “immediate steps to change completely” how it publishes reports containing sensitive forecasts after it mistakenly released an analysis of the Budget early last week.
This could either be by moving publishing arrangements for the OBR to the Government’s independent subdomain or by passing the publication of the two annual forecasts to the Treasury, the watchdog said after probing the incident.
The OBR launched an investigation with expert input from Professor Ciaran Martin, former head of the National Cyber Security Centre (NCSC), after official forecasts were uploaded to the watchdog’s website, releasing details of the Budget almost an hour early.
It deemed the leak of its Economic and Fiscal Outlook (EFO) before last Wednesday’s Budget to be the “worst failure” since the watchdog was created by George Osborne as Conservative chancellor in 2010.
In the foreword to the report, Baroness Sarah Hogg and Dame Susan Rice, non-executive members at the OBR, said of the early publication: “It is the worst failure in the 15-year history of the OBR.
“It was seriously disruptive to the Chancellor, who had every right to expect that the EFO would not be publicly available until she sat down at the end of her Budget speech, when it should, as is usual, have been published alongside the Treasury’s explanatory Red Book.
“The chair of the OBR, Richard Hughes, has rightly expressed his profound apologies.”
It was “not a case of intentional leakage”, according to the report released on Monday, or a matter of pressing publish too early.
The OBR said it was caused by two errors linked to the WordPress publishing site it used.
The report into the incident said that, while it knew web addresses for its files follow a pattern, it assumed “the protections provided” by WordPress “would ensure it could not be accessed”.
But two configuration errors were the technical causes of the premature access.
The report of the investigation into the November 2025 EFO publication error has now been published on the OBR's website: https://t.co/er1Lj1bWv1
— Office for Budget Responsibility (@OBR_UK) December 1, 2025
The forecast for the last spring statement in March was also “accessed prematurely” on one occasion, the report noted, but concluded that no activity appeared to have been taken as a result and the most likely explanation is “benign”.
The report recommended a review of the watchdog’s processes for publishing such documents.
“To rebuild trust, the leadership of the OBR must take immediate steps to change completely the publication arrangements for the two important and time-sensitive documents containing the results of its biannual forecasts that it publishes in a normal year, and review arrangements for all other publications,” the report said.
One option would be for the watchdog could use the Government’s digital architecture but publish when it wants.
Another would be to have the Treasury publish the forecasts for the Budget and spring statement, but this would only work if safeguards for “real and perceived independence” could be put in place.
There may need to be an interim solution, the report noted, but said new arrangements must be in place in time for the next statement in spring 2026.
A Treasury spokesperson said: “We thank the Office for Budget Responsibility for their report. The Chief Secretary to the Treasury will respond in due course.”
