National's Christopher Luxon has committed to raising the age of superannuation should the party get into power.
The party intends to lift the age of eligibility from 65 to 67, despite a recent report from the Retirement Commission recommending the age stays the same.
The report said the commission had concerns that raising the age might disadvantage manual workers and groups with lower life expectancies, including Māori and Pasifika.
Luxon said increasing the age would be done gradually and the party was giving people 15-20 years' notice.
But it needed to be done, he told Morning Report.
"Every decade people live 1.3 years longer. It's not an unreasonable thing and other countries have already fully adopted 67 as a retirement age.
"It's the sensible, pragmatic, practical thing we have to do."
When asked, Luxon was unable to say how much money a person living alone on superannuation was paid a week.
But he said the amount and how they survived off it was a different issue.
"That gets us back to economic mismanagement in this country and why we need a strong economy that drives into higher wages and creates more wealth so we can actually afford to support people in a better way."
Raising the age was "the right thing to do" for the country.
There was going to be a rising level of cost, people were living longer and the country was struggling, he said.
"I've been the leader now for a year. Every quarter it has got worse, our economic outlook and conditions, and the government's done nothing to adjust."