"The bank accepted the fictitious transactions," the SFO said in a statement.
However, the properties were sold for a higher priced than he stated or were transferred to another trust and refinanced with a loan from another bank.
In January 2012, Johnston submitted a false Statement of Assets and Liabilities to the bank when obtaining the refinanced loan.
SFO director, Julie Read said the offences were a result of an attempt to avoid a troubled financial situation.
"The reality is that in deceiving the bank Mr Johnston has placed himself in a much more serious position which will result in a criminal conviction.
"Such a course should never be considered as a viable option and the SFO will prosecute all serious fraud matters brought to our attention to protect other investors and New Zealand's reputation as a corruption free market."
Johnston will be sentenced in November.