Van Heerden has penned a three-year contract with the Chilli Boys.
"Executive Chairman Chippa Mpengesi has confirmed the signing of left-back Marc van Heerden on a three-year deal," United announced on Twitter.
Van Heerden later expressed his delight to be back in the topflight.
"Super excited to be back in the #PSL with @ChippaUtd. Thanks to all involved espes my Amazing mentor @MikeMakaab as well as Mr Mpengesi," he tweeted.
Usuthu transfer-listed the 28-year-old after their failed bid to seal an immediate return to the Absa Premiership last season.
Van Heerden joined the Durban-based outfit in 2008 from University of Pretoria.