The legislation had been planned to come into effect in April.
Labour Minister Mr Bridges said paying young people less for the same work was creating an incentive to employers to hire young people.
"The truth of the matter is the vast majority of New Zealanders see the absolute sense in this; it's about creating job opportunities for young New Zealanders.
"I think they will be paid fairly. I tell you what, I'd rather be on a reduced wage as a young person with a chance of promotion and a step up than no job at all."
Mr Bridges said he worked a number of low-paid jobs in his youth.
He said research showed that young people who did not have jobs in their early years would have poorer health, social and economic outcomes.
Labour's labour spokeswoman Darien Fenton said the bill reintroduced youth wages, something that hadn't been seen in New Zealand since the 1990s.
"Paying young workers to do the same job for less just because of their age is discriminatory and unfair and will have little, if any, impact on youth employment levels."
She said the move would discourage young people from seeking work and encourage bad employment practices among employers.