Almost seven in 10 Post Office sub-postmasters have experienced an “unexplained discrepancy” on the Horizon IT system since January 2020, a survey has revealed.
It suggests faults remain in newer versions of the accountancy system still used by the Post Office, which has been at the heart of one of the worst miscarriages of justice in British legal history.
A poll of sub-postmasters by YouGov found that almost all of those who had difficulties with Horizon reported shortfalls in their accounts and most resolved them by using their branch’s money.
An inquiry into the Post Office scandal resumes on Monday and will focus on how the company, which is wholly owned by the government, operates today.
Between 1999 and 2015, more than 900 sub-postmasters were wrongly prosecuted after faulty software called Horizon made it look like money was missing from Post Office branch accounts.
Despite this, a version of the Horizon IT system is still in use in UK Post Offices.
YouGov said it found that nearly half of the sub-postmasters it spoke to were “dissatisfied with how the Horizon IT System currently operates”, compared to 25% who were happy with it.
It added: “The vast majority – 92% – of sub-postmasters surveyed reported experiencing some form of issue with the Horizon IT system in the last 12 months.”
“In my opinion Horizon is still flawed I regularly have unexplained discrepancies often altering daily or manifesting at balance,” one sub-postmaster YouGov.
The most common problems reported were screen freezes and loss of connection, while more than half said they had experienced “unexplained discrepancies”, and others mentioned seeing unexplained transactions.
YouGov was commissioned to carry out the research by chair of the inquiry Sir Wyn William. It invited 6,532 current sub-postmasters to take part in its survey between 18 July and 15 August – 1,015 people responded.
The BBC has contacted the Post Office for comment.
It also held a second survey regarding compensation payouts relating to the Horizon Shortfall Scheme (HSS). It found nearly half of HSS applicants surveyed were dissatisfied with the scheme.