Kate Sluka, finance research writer at Consumer New Zealand, said the offers added to a plethora of low interest rate and low fee cards which had been introduced into the market in the past few years.
"There are a lot more variety of cards on offer than there was five years ago."
Sluka said ASB was the first mainstream bank to offer a zero per cent interest rate on a credit card although its short offer period of five months meant it was more of a "teaser" than a permanent change.
"It looks like ASB is trying to compete with the store cards."
The ASB offer applies only as long as people pay the minimum balance and the card is still subject to an annual fee.
Sluka said some store cards were offering zero interest and zero payments for a set period of time but warned the catch was often in the higher annual fees charged.
Zero interest could be very attractive as it made people think they had time to pay off the debt, Sluka said.
But she warned those considering a card switch to make sure they read the terms and conditions first so they knew what they were in for after the interest-free period runs out.
"If you don't think you can pay it off in that period - don't touch them."
It was also important to find out the fees for cancelling the card or making late payments.
Adam Beu, a research analyst in Australia with financial products rating firm Canstar, said more than 60 different credit cards were available in New Zealand although the number of companies offering them was still fairly small.
"The offers from institutions have diversified. It's no longer just about rewards or low interest rates."
Beu said the diversification was driven by consumers wanting more options.
In Australia credit card providers competed on balance transfer deals and introductory offers. Currently consumers there could get up to 15 months interest free on a balance transfer.
Others had linked their credit cards to home loans to offer low interest rates. The BNZ deal was "fairly unique in New Zealand" but was similar to Australian offers, he said.
Shaun Drylie, ASB's general manager of product and strategy, said credit cards were a hugely competitive space.
"The level of competition is pretty intense."
Drylie said the bank saw credit cards as an important way to tap into the future of mobile banking.
"You're going to see quite a lot of innovation in the mobile space."
Drylie said it was not about the plastic card itself but the ability to pay using mobile phones.
He predicted more innovation to come in the credit card area.
Drylie said around half of ASB's credit card customers paid no interest by paying off the full balance of their card every month.
Plastic war
• $5.6 billion credit card market.
• ASB launching 0% interest for next five months on new cards.
• BNZ offering a variable home loan interest rate on its card.
