Edias Mazambani, 42, pleaded guilty to fraud by abuse of position on 3 September 2025, during a trial at Southwark Crown Court.
The trial, which began on 1 September 2025 and lasted for six weeks, also saw four others convicted of money laundering.
George Magaya, 48, pleaded guilty to four counts of money laundering, during the trial, on 3 September 2025.
On 14 October 2025, the jury found Rosemary Magaya, 37, and Michelle Tengende, 40, guilty of money laundering. Both were employed by the NHS at the time of the offences.
The jury also found Sinqobile Pasipanodya, 43, guilty of money laundering.
All five had previously pleaded not guilty to all charges at a hearing at Southwark Crown Court on 9 November 2023.
They have all been released on unconditional bail ahead of sentencing, expected in January 2026.
The fraud was uncovered by staff within the finance department at Guys and St Thomas NHS Foundation Trust after they identified suspicious refund requests relating to monies held on behalf of patients and clients.
Internal investigations revealed the involvement of a trust employee, Mazambani, who had access to secure financial databases. Further checks confirmed links between him and the bank accounts receiving fraudulent payments.
NHSCFA financial investigators used their powers under the Proceeds of Crime Act 2002 (POCA) to trace the stolen funds. The investigation revealed that Mazambani had facilitated fraudulent refund claims, and that money had been transferred to accounts linked to the other defendants.
Following his arrest, Mazambani provided a "no comment" interview. Documents relating to trust refunds were recovered from his home address.
The investigation identified over £218,000 in fraudulent refunds paid out, with an additional £84,000 in fraudulent claims prevented, bringing the total fraud value to over £302,000.
Financial analysis revealed the four co-defendants received substantial funds through the fraudulent scheme, which were subsequently transferred back to Mazambani and the Magayas in most cases.
Ben Harrison, Head of Operations at the NHS Counter Fraud Authority, said:
“This was a sophisticated internal fraud that exploited the trust of patients and the NHS system.
“Mazambani used his privileged access to confidential financial data to steal over £218,000 and attempt a further £84,000 involving accomplices to launder the proceeds.
“Our investigation, working closely with the trust's finance team, demonstrates that we will pursue fraudsters wherever the evidence leads and use all available powers to recover stolen NHS funds.”