The National and Labour donations cases are set to be heard from Monday in a combined trial set down for 10 weeks.
Yikun Zhang, Shijia (Colin) Zheng and Hengjia (Joe) Zheng are facing charges laid by the Serious Fraud Office (SFO) relating to two $100,000 donations to National in 2017 and 2018, and donations totalling at least $34,840 to Labour in 2017.
Former MP Jami-Lee Ross is also defending in relation to the National donations.
Three other people whose identities remain suppressed are also accused over the Labour case, none of whom are sitting MPs or current or former Labour officials.
All defendants in both cases have denied all charges - of obtaining by deception - which relate to what the Crown will argue was attempts to hide donors' identities and amounts.
Joe Zheng also faces a charge of supplying false or misleading information.
The SFO began investigating the National Party donations after Ross himself took a complaint to police in 2018, following after a fallout with then-leader Simon Bridges.
He secretly recorded a phone conversation between them which he argued proved Bridges had not declared the donations correctly and was therefore guilty of breaking electoral law. Bridges denied the allegation and has never been charged over the matter.
Charging documents accuse the defendants of obtaining a $100,000 donation for the National Party in 2017. The donation was allegedly broken into amounts less than $15,000 and transferred into seven different bank accounts before being transferred to National.
The defendants are also charged over a further $100,050 donation in 2018.
The Labour Party case relates to the purchase of five paintings from Labour for $60,000 in 2017. The SFO again claims the payment was split between five different names to give the illusion of five separate donations.
Zhang also purchased an Imperial Robe and two other items at a Labour fundraising auction for $100,000 in September 2017.
The case is set down for 10 weeks in the High Court at Auckland.
It follows the conclusion of another case, relating to the handling of more than $700,000 in political donations by the New Zealand First Foundation over five years. The defendants in that case were found not guilty, and have permanent name suppression.
The government is also working on stricter rules relating to donations, which include lowering the identification threshold to $5000 a year.
Parties would also be required to publish their financial statements, the number and total value of non-anonymous donations below $1500, and the proportion of total non-monetary donations.
Opposition parties National and ACT argue the court cases show the law is working as it should and does not need to be changed. The Labour government says the changes will lead to greater transparency.
A review of electoral laws is also under way, although many of the potential changes that considers have been reviewed before and remained unchanged.
Any changes that review led to would need to wait, too, until after the election next year.
RNZ
