"I think that the ACT brand has just about had its use-by date," ACT's sole remaining MP John Banks told Radio New Zealand's Checkpoint programme this evening.
Mr Banks said it was time to take stock, rebuild and rebrand the party.
The rebranding could include a re-launch with a new name, the Epsom MP said.
Mr Banks added that, on a personal level, he got along well with Colin Craig, leader of the socially conservative Conservative Party - hinting at a possible direction for an Act restructure.
The Conservatives gained 2.76% of the vote on Saturday.
His comments caught a later interviewee on the programme - Former Federated Farmers president Don Nicolson, number three on the party's list - unawares.
Mr Nicholson said he was unaware of any rebranding or name changer exercise. He assumed Mr Banks had discussed the matter with the party's board.
Although Mr Banks won Epsom, ACT's party vote nationwide fell to 1.07%, reducing its number of MPs from five to one.
Mr Banks said ACT would not rush into choosing a new leader, who would not necessarily be himself.
Don Brash resigned as leader on Sunday.
Catherine Isaac, number two on the ACT's list, said earlier today she was not seeking an active role in the party.
Mr Nicholson said leadership could be in his future, but that he would have to get closer to the party's management.