The Opportunities Party founder, Gareth Morgan, spent more than $2 million on his party's unsuccessful election campaign.
According to declarations on the Electoral Commission's website, Dr Morgan donated $2.13 million to TOP between April and October.
That makes him easily the largest donor to any political party this year.
The next largest donor was a company, the Inner Mongolia Rider Horse Industry NZ, which donated $150,000 to the National Party. The company is a horse breeding outfit owned by Chinese billionaire Lin 'Mr Wolf' Wang, that exports thoroughbreds to Mongolia.
Labour's biggest donor was the E tū Union, which donated $120,000.
The Dairy Workers Union also donated $100,000 to Labour.
Apart from Dr Morgan, the highest sum donated by an individual was by the retired High Court judge Robert Smellie, who donated $115,000 to the Labour Party.
TOP received just 2.4 percent of the vote, less than half of what it needed to get list MPs into Parliament.
The next biggest political donor in the last three years was the estate of Elizabeth Riddoch, which donated $283,000 to the Green Party in 2016.
Another big donor in 2015-2016 was the Conservative Party founder Colin Craig.
Although he no longer leads the party, Mr Craig was its major funder, donating $166,000.
The Conservative Party got just 0.2 percent of the party vote.