Prime Minister-designate Jacinda Ardern says she will ease the pressure of higher wages on small- to medium-business owners, including looking at a lower company tax rate.

As part of its deal with New Zealand First, the incoming Government will raise the minimum wage from $15.75 an hour $16.50 next year, and then to $20 by April 2021.

The increase is raising concerns in the business community and among farmers about meeting higher costs.

Speaking to Radio NZ's Morning Report, Ardern said she wanted a tax working group to look at how Australia's stepped tax regime operates.


"They have a slightly lower corporate tax rate for companies and businesses that have lower turnover. I'm interested in how we can ease the burden on small businesses in particular."

In Australia, companies with turnover of less than $10 million a year pay a lower company tax rate.

"This is me foreshadowing that I do have a genuine interest in how we can support those who create jobs in New Zealand," Ardern said.

"In large part, our small and medium enterprises - well over 40 per cent of our new jobs - are coming from our SMEs. I want to do all I can to work in partnership with them."

Ardern has said that any tax working group recommendation on a capital gains tax would not be implemented in this parliamentary term. But she said a recommendation helping small businesses could be introduced before the next election.

National's finance spokesperson Steven Joyce said the wage increase will make small businesses less competitive and reduce their hiring ability.

"The Government of the day has just arrived and it's telling you the wages of your lowest paid workers are going to go up 27 per cent over the next four years, in an inflationary environment of 1 to 1.5 per cent, maybe 2 per cent," Joyce told Morning Report.

He said National's tax cuts, which the incoming Government plans to cancel, would better serve low-paid workers.


"Why didn't she just stay with the lowest band income tax cuts between $14,000 and $22,000? If you really care about low-paid workers, that would give them immediately $11 a week fro April next year.

"Instead, they're going to place the burden on all the small business owners. They're basically saying, 'You over there, you small businesses, you're going to get squeezed because we can't keep our costs under control.'

"And that's the way they're starting off."

Ardern said Labour's 100-day plan would look to quickly put into place, among other things, its families package, tertiary education policy and the minimum wage increase.

Joyce said he would be keeping an eye on Labour's expenditure.

"I don't want to be right, but I can tell you they've just allocated the first $3 billion of their $4 billion over the next three years."