Optus will stop allowing third-party subscription services like mobile games to charge their fees to telecommunications bills from the end of January next year.
The move follows long-time issues with the practice that similarly prompted Telstra to ditch third-party subscription billing in August.
The practice allows subscription-based mobile games, apps, and videos to add their charges onto the user's phone bill. It can also be used for one-off charges like an app or voting on a reality TV show.
It is achieved through HTTP header enrichment, which sees a customer's number passed on from a telco to the third party to allow for the purchase to be added to the user's telco bill.
But while initially intended to make billing easier for subscription services, abuse of the process has seen people receive random charges for services they didn't purchase.
A separate scandal erupted in 2015 when it came to light that US telco Verizon had been using HTTP header enrichment to track and identify its users to advertisers. Telstra and Optus both admitted to doing the same at the time.
In response telcos have implemented encryption to stop the third party from being able to see the customer's number until the transaction is completed. Telcos have also opted to limit the number of subscription services they partner with.
Optus earlier this month revealed it would follow Telstra's lead and ditch billing for third-party content subscription services entirely.
"We know it can be frustrating when an unexpected third party content charge appears on your Optus mobile bill," it said.
"We constantly review our relationship with content providers to ensure we’re offering our customers the best mix of services and content offerings.
"But we’ve also listened to examples that you have experienced in regard to third party content so from 31 January 2018, we’re suspending certain subscription-based third party content providers on all mobile services that use the Optus network (except Virgin Mobile Australia customers)."
The policy change will not impact subscriptions and purchases made through the likes of Google Play, or for Netflix and Spotify.
Optus will still allow one-off content purchases such as for TV voting and and charity donations on its mobile network. Subscriptions that have existed before January 31 2018 will similarly not be impacted.
But both one-off and subscription purchases will stop entirely for those on mobile broadband and home wireless broadband Optus services from that date. Existing subscription services will also cease.
The telco said the effort was intended to reduce the instances of customers being unexpectedly charged by third-party content providers.
Fellow telco Vodafone has not offered third-party subscription services since 2015. It only allows one-of purchases through HTTP header enrichment using encrypted phone numbers.