The Office for Budget Responsibility (OBR) has revealed that the leak of its fiscal report before the Budget was due to “technical errors” made by staff, with the same error in March meaning the Spring Statement was also accessed before Rachel Reeves delivered her statement in the House of Commons.
The fiscal watchdog published a review stating that “weaknesses” existed in its protections of confidential documents before the Budget process, leading to its “worst failure” in the OBR’s 15-year history when its report leaked before Reeves announced new policies last week.
The report also said that measures in the Spring Statement were also “accessed prematurely” in March 2025, though it suggested there was “no evidence” that details were used to anyone’s advantage.
The main technical errors involved problems in the use of a downloading function, which left the document unprotected, and with WordPress, which is used to manage the website.
In the review by Professor Ciaran Martin, a former National Cyber Security Centre chief, it was also confirmed that there was no “hostile cyber activity” involved in the early release of the report.
Non-executive OBR officials Baroness Hogg and Dame Susan Rice said the body should look to find any other examples of premature access to fiscal reports.
OBR chiefs concluded they would change the way they published Budget reports, suggesting the Treasury should take greater oversight of publications given the body’s small size.
It also urged other departments in the public sector to review how they handled “sensitive material”.
OBR reveals full timeline of events
The review said the first attempt to access the document was made at 5:16am on the morning of the Budget.
The pages were only uploaded at around 11.30 to the “draft area” of the website, which workers at the body believed to be inaccessible to the public.
Around 15 minutes later, first notice of the Budget appeared in a Reuters news flash. A journalist told an OBR representative that Budget details had been published in the media shortly after.
It was only after Prime Minister’s Questions had started at 12pm that the OBR took the report offline before it posted on X to confirm that the Budget had been leaked.
Mel Stride then raised a point of order to complain about the leak, with Reeves nodding her head to the Shadow Chancellor’s criticism.
Earlier on Thursday morning, Keir Starmer said the leak was a “massive discourtesy” to parliament to release “market sensitive” information.
The government has previously expressed its confidence in OBR chair Richard Hughes, who is set to appear before MPs on Tuesday morning to answer questions about the fiscal report.