Spark has been running a one-day trial of online-only support for its prepay customers.
The company told customers calling through on Wednesday that the trial was currently underway, and those customers were directed to the Spark website instead.
"Prepay customers can get pretty much everything they need done online - whether that's through the Spark app, or talking to one of our team on Chat," Spark's senior communications partner Ellie Cross told Newshub.
"Plus, many pre-pay customers are comfortable managing their account using the app. So we are running a trial to see how our customers find being asked to head online to get things done."
The trial is part of a "broader move" by the New Zealand telecom operator towards encouraging customers to use its digital tools and services.
Ms Cross said it's often quicker to speak to a member of the Spark help team using its live Chat resource than it is to wait to speak to someone on the phone.
"In today's world, when a quick and simple way exists to get something done online, we often find that people prefer this to waiting to talk to someone on the phone," she said.
"However, we do know that there are times when you just need to speak to someone at Spark. So although we're encouraging customers to head online, they can still speak to one of the Spark team if they need to."
The trial is just for pre-pay customers, not other services.