Mining magnate Clive Palmer poured more than $7 million into his party's political coffers, while the big four consultants gave hundreds of thousands to major parties and environmental advocates dug deep in their pockets for teal independents.
The Australian Electoral Commission on Thursday published data on donations made in the past financial year.
The register shows Mineralogy, the mining company owned by Mr Palmer, donated $7,088,867 to the United Australia Party in 2022/23.
Climate 200, a company that provided funding to the campaigns of teal independent candidates at the 2022 federal election, received major personal donations.
Environmental advocate Marcus Catsaras stumped up $1 million to the climate advocacy group.
Share trader Rob Keldoulis made a number of personal donations worth $702,113 to Climate 200 between October 22 and May 2023.
His company Keldoulis Investments, also supplied cash to the tune of $365,430 to the group.
PwC, which was taken to task for leaking confidential tax office information in a major scandal, made a series of donations totalling $369,973 to both the Labor and Liberal parties between July 2022 and May 2023.
Other large consulting firms also donated money to the major parties, with EY shelling out $227,853, Deloitte $177,126 and KPMG $163,200.
Perth-based company Hadley Holdings made two donations totalling $1,025,000 to Advance Australia in November 2022.
The self-described anti-leftist political lobby group funded campaigning against the Indigenous voice to parliament referendum held in October 2023.
Pratt Holdings donated $1,010,500 to the Labor Party in January and March of 2023, with $500 sent to the NSW branch.
Parties and individuals are required annually to disclose donations of more than $15,000 under current rules.
Integrity advocates, including the think tanks Centre for Public Integrity and Australia Institute, have called for reforms to address record-high election spending and donor transparency.
Analysis by the centre in 2023 found election spending had increased by almost 85 per cent in the past two decades.
In 2022, the most recent federal election year, spending reached a record high of almost $440 million and the top five individual donors contributed 70 per cent of all donations.
A similar analysis by the Australian Democracy Network also highlighted that nearly on quarter of all donations, about $50 million, came from undisclosed sources.
Australia Institute director Bill Browne said the electoral commission's annual release highlighted the lack of transparency and integrity in Australian politics.
"We are learning today whether businesses made political donations 18 months ago," he said.
"These lags and other loopholes make it difficult to see how politicians and political parties are being funded and by whom."
The Foundation for Alcohol Research and Education noted $1.3 million had been donated by companies that profit from alcohol.
Its chief Caterina Giorgi called for a ban on these donations claiming it created a power imbalance that prioritised business interests over the wellbeing of Australians.
The institute wants real-time donation disclosures introduced, a lower donation disclosure threshold and ministerial diaries to be made public.
This would reveal if there were any connections between political contributions and political access.
Mr Browne said there was limited time for changes to come into effect ahead of the next federal election.
"This is a wake-up call that 2024 is the last chance for meaningful democratic reform ahead of the 2025 election," he said.
