The minimum wage for New Zealand adult workers has been set at $14.25 per hour. It connotes an increase of 3.6 per cent of 50 cents over the previous $13.75. The new salary scheme will take effect on April 1.

As expected, labour unions blasted the measly rise. While the sector heralded the act, the steep figures were unfair and insufficient.

"We've been saying at least $15 for quite a while, and I've said yesterday not only will we raise it to $15 in our first hundred days, but we'll raise it again six months later in our first year - April or May," David Cunliffe, Labour leader, said on TV ONE's Breakfast.

Bill Rosenberg, Council of Trade Unions economist, said the increase should have been made to $15.50 this year, 2014, to compensate for the several years of stagnating wages.

"The minimum wage is the only way, other than through the tax and benefit system, that the Government has to ensure wage and salary earners, and particularly people on low incomes, benefit from a growing economy," he said.

"Instead almost half of employees are getting no wage or salary increases at all. This minimum wage increase goes little distance to addressing the inequalities in society."

Prime Minister John Key, in announcing the wage hike on Monday, maintained increasing the minimum wage above $14.50 would result in job losses.

"We're trying to balance the capacity for businesses to pay a bit more and for people to earn enough to live," he said.

Kim Campbell, CEO of the Employers and Manufacturers Association, said the group can bear with the figures, noting New Zealand businesses will still be able to manage.

"It is coming in small increments, so industry will probably be able to cope with it," he said.

More than 100,000 low-paid workers, mostly young people and part-time employees, are expected to benefit from the pay rise effective April 1.

The Starting-Out and training minimum wage will likewise increase from $11 to $11.40 an hour, to keep them at 80 per cent of the adult minimum wage.