Around 13% of invoices received by the government are not paid within 30 days, according to the Treasury.
The admission comes after a hospital patient had their cancer screening appointment rescheduled.
They were told it was because there was no cleaning solution for the equipment.
In an email to States Members, seen by Channel 103, it was alleged that medical the staff told the patient that it was because the supplier had stopped delivering due to unpaid bills.
However, the Health department told us it has investigated the matter and that wasn't the case.
"We are aware that an order was not fully delivered. Following investigations, it is clear this was caused by an issue with the delivery company and not by unpaid bills.
There was sufficient stock available on-site within other departments and we are looking into why this was not used, or an alternative procedure was not offered.
We apologise for any distress this has caused and we are working to resolve it as a priority. We are working with suppliers and clinicians to prevent this from happening again."
A new payment system called 'Connect' is being rolled out across all States departments, which has been labelled as 'far too complicated'.
In March, it was revealed that the move to the new system had uncovered unpaid bills from before 2022, reportedly totalling £6 million, which the Minister called 'clearly unacceptable'.
Extra staff were brought in to clear the backlog.
Officials say they're working 'proactively' with suppliers to make sure critical medical supplies are available.