The penalty fees will apply for August bills onwards.
Vodafone spokeswoman Michelle Baguley said the new charges would affect only a minority of customers.
"It's true that the majority of our customers do pay their bills on time. But the cost of recovering payments from those who don't is significant.
"And the late-payment is going to help recoup some of those costs, and has been a standard industry practice for some of our competitors for a little while.''
Telecom charges a late payment fee of either $14 or 1.66 per cent of the outstanding bill - whichever is greater.
But a 2Degrees spokeswoman said the network did not charge late payment fees and had no plans to do so.
Ms Baguley said Vodafone was reminding its customers that the easiest way to avoid the penalty fee was to set-up a direct debit.
"What we've decided to do...is target specific people [chronic late-payers]. What it means is it doesn't have any impact on everybody else.''
But Vodafone customer Esther MacIntyre, a producer at 95bFM, said the fee would net customers such as herself who might occasionally forget to pay a bill.
She said the cost of sending such customers a reminder text or automated phone call was not great.
"I'm not going to stop using your service, I need a phone, and I have the money. Sometimes I forget to pay a bill, like everyone.
"You're not supposed to treat your customers like this, because people will leave. It just seems really basic to me.''
The 23-year-old has been with Vodafone since she bought her first phone in high school and said she found the company's approach rude.
"It's kind of passive aggressive - 'Hello Esther, most people try to pay their bill when it's due. However, this isn't always the case.'''
See tomorrow's NZ Herald for more on this story