Online access is getting more expensive and Internet New Zealand says the increases are not justifiable.
Spark, Vodafone and Callplus together represent 94 percent of the residential internet market and all have put up their prices for home internet packages.
Internet service providers blame the rises on the Commerce Commission's recent draft decision which reduced the price companies pay for use of the copper wire network.
The Commission had intended to reduce the price from $45 a month to $33.44 but decided to settle on a figure of $38.39.
Internet providers say they have adjusted their prices to reflect that final higher price.
Internet New Zealand work programme director Andrew Cushen said these companies took a gamble and consumers are the victims of it.
"What that's resulted in ... was not them losing out but the customers of New Zealand losing out; the internet users of New Zealand having to pay the price for them rolling the dice in terms of a lower set of prices that didn't eventuate."
Chief executive for Spark Home, Mobile and Business, Chris Quinn, said while the prices are going up, services are also better, with offers such as unlimited internet access at a fixed price.