One of the charities New Zealand First gave money to has returned the donation.
Party leader Winston Peters announced on Sunday the $158,000 it wrongly spent during the last election had been shared out to "worthy causes" but would not identify them.
The Cystic Fibrosis Association announced last night it had decided not to accept NZ First's $10,000 donation, The Dominion Post reported.
Association chief executive Kate Russell said it was unclear whether the party had the right to give the money to charities.
NZ First initially wanted to give all the money to the Starship Hospital, but the board turned it down for the same reason.
Auditor-General Kevin Brady decided NZ First used the $158,000 of taxpayer money outside the rules for election spending.
All the parties in Parliament except the Progressive Party were caught in the same trap, and paid back the money, but NZ First insisted it had been given prior clearance by Parliamentary Services.
Critics say NZ First doesn't have the right to give away taxpayer money to charity and it should be repaid to the service.