The territory's electoral commissioner says he will ask the ACT Liberal Party to explain inconsistencies in its reporting of donations it received in 2012-13.
Commissioner Phil Green said he would examine a $73,000 discrepancy between gifts of money the division disclosed in its annual returns and the disclosures it reported to Elections ACT during the financial year.
On Monday, Elections ACT published the 2012-13 financial data for ACT political parties.
The annual returns show ACT Labor spent $1.5 million during the year, which included the ACT election campaign.
The Canberra Liberals spent $953,800, while the ACT Greens tripled their spending on the previous year to $653,800.
ACT Labor appears to have reduced its debt to $11,240 and the Liberals to $47,161 but the ACT Greens' debt has grown to $54,020.
The returns also list gifts, receipts and anonymous donations to all ACT political parties.
Under electoral disclosure laws, parties must report gifts of more than $1000 to Elections ACT within 30 days of receiving them and within seven days during an election campaign. During 2012-13, the Canberra Liberals declared $59,000 in gifts of money to Elections ACT. The annual return published on Monday lists $132,000 in gifts of money.
''It would appear that the two aren't consistent and we'll be investigating why they aren't consistent,'' Mr Green said.
''A possible explanation is to do with the definition of gift.
''We'll be looking at this discrepancy and asking what's going on.''
Elections ACT data shows the ACT Labor Party reported $19,000 in gifts of money but the annual return lists $1800 in gifts of money and $7500 in gifts of money and receipts.
An ACT Liberal Party spokeswoman said the Canberra Liberals' discrepancy was due to the different reporting requirements for annual returns and the ongoing disclosures of donations to Elections ACT.
''The ongoing disclosure requires that every gift over $1000 has to be disclosed,'' she said. ''However, with a gift, we are able to account for up to $250 as costs for the event that the person attended. The annual report requires that every receipt over $1000 has to be disclosed.''
The spokeswoman said the different reporting rules meant the figure in annual returns was always higher than the ongoing report.
Mr Green said the major parties would be audited in coming months.
''This is really the first time that parties have had to put in annual returns in this level of detail,'' he said. ''So it's not surprising that there might be some discrepancies thrown up. The audit process will look at that.''