Last month Verizon added new charges to its customers' phone bills, and it isn't done with increases. The carrier confirmed to CNET on Friday that it will raise rates for those on its older, shared data plans with their next bills. 

"Verizon's unlimited plans provide customers with the most value in the industry along with the peace of mind that their plan cost will not increase no matter how much talk, text or data they use," a Verizon spokesman said in a statement. "While we recommend our Shared Data Plan customers migrate to an unlimited plan to take advantage of all we have to offer, we are not requiring it.

"That said, for the limited number of consumer customers remaining on these accounts, we will be introducing a rate plan adjustment in their next bill to account for the added cost of maintaining these legacy plans."

Verizon has confirmed to CNET that the "adjustment" will be $6 extra per month for single lines. Those with multiple lines on an account will be charged $12 more per month, for the entire account and not per individual line. 

The carrier will be messaging affected customers about the increases starting next week, with the extra cost coming into effect on their next month's bill. 

YouTuber Tech Life Channel first reported on the new charges in a video.

The move comes as Verizon continues to look for ways to migrate users off of shared data plans and onto unlimited plans. While the carrier is not forcing users off of shared data plans, access to its faster 5G networks and its most aggressive device trade-in promotions have required being on one of its pricier unlimited options. This new increase is the latest, and most aggressive, nudge to get people to give up older plans.

Rival AT&T announced a similar price hike for nonunlimited plans in early May, citing higher business costs as a justification. Like Verizon, the carrier raised single lines on shared data plans by $6 per month, while family plans went up by $12 per month.