The balance swung in Mr Moffat's favour when he decided to take some leave.
He applied for 26 days' holiday pay and when he received his education services payslip found it showed an hourly rate of $658,800.
Normally Mr Moffat, who works a six-hour day, is paid $16.09 per hour.
Mr Moffat joked to the Otago Daily Times yesterday about how he might spend the overpayment but actually hoped the money did not appear in his bank account today.
''I don't want it to go in, because it will just be a lot of trouble. But it's totally bizarre.''
The school's executive officer, Helen Hammond, described the hourly rate on Mr Moffat's payslip yesterday as ''a nonsense'' and was reasonably confident the new system would not pay out such a large sum in error.
''There have been some strange things happening in the pays but I think if it was something as bizarre as that it would get picked up - hopefully.''
Ms Hammond noted the hourly rate anomaly was not carried over into the main calculations on the payslip - which show holiday pay of $0.00.
Her reading of other information on Mr Moffat's payslip led her to believe he would get his holiday pay but not the huge amount suggested by the hourly rate figure, and she had not brought this particular error to the ministry's attention.
''I think all we can do is wait and see what actually comes through in his pay.''
A spokeswoman for the Ministry of Education said Mr Moffat ''definitely'' would not be paid that amount.
Some payslips had been inaccurate because of processing errors and the ministry was ''working hard to ensure these errors are corrected''.
- Mr Moffatt has checked his bank account today and the over-payment did not appear.