Spark also confirmed it is relaunching Jump, its cut-price fixed-wireless product for low-income familes, which has been used to connect some 5000 low-income families since 2016.
Earlier, country's third-largest internet service provider has wiped data caps for customers in its stable amid the coronavirus scare and a surge in working from home.
"We have removed datacaps for Flip and Slingshot customers. All of Orcon was already unlimited," a Vocus spokesman told the Herald.
Those on cheaper plans who usually have to buy extra data packs when they bust their limit have been upgraded to unlimited accounts at no cost.
"We didn't press-release it as we are just trying to do the right thing. We told customers last night," the spokesman said.
The move is for an open-ended amount of time. It only applies fixed-line broadband, not mobile.
All three ISPs are part of Vocus, the number three player in the broadband market behind Spark and Vodafone.
Spark and Vodafone did not have immediate comment but a spokesman for 2degrees, the number four player in the landline market, said "96 per cent of 2degrees customers are already on unlimited broadband data plans, so they don't need to worry about using data."
He added, "We're making a change so that the small percentage on 80GB capped plans won't pay more than they would for an unlimited plan.
The difference between our 80GB capped 2degrees broadband plan and Unlimited is $10 a month.
"If a customer on a capped plans continues to use less than 80GB, they'll continue to pay $75 per month. But if they're using a lot more data, their bill won't go beyond $85 a month," the spokesman said. Contract mobile customers will get $10 off.
2degrees will review the situation in two months.
The Herald has asked Spark, Vodafone, if they plan to follow suit, along with number four and five broadband players 2degrees and Trustpower.
The Commerce Commission's Annual Telecommunications Monitoring Report 2018, released earlier this month, said the top five players hold 89 per cent of the fixed-broadband retail market.
Unlimited data caps will be boon for people working from home, and employers who have to cover remote access connections - or any overage.
But a Statistics NZ study in 2018 found most of us are already there, with some 70 per cent of households on unlimited plans.
Yesterday, InternetNZ called on the government and private industry to work together to ensure there was universal internet access.
"The Internet is absolutely critical to our country and people getting through this situation. Universal access to the Internet is part of that, and so we need to see digital inclusion improvements as part of the next phase of the Covid-19 response," Carter told the Herald.
"This is important given that so much of the official information about Covid-19 and the response is being distributed by the Government online," Carter said.
The InternetNZ boss said subsidies and free hardware for low-income households were one possible mechanism, but he saw such Crown initiatives working in tandem with projects like Spark's Jump initiative, which offers cut-price internet to children in low-decile areas (the telco is due to announce an expansion of the programme later this week).