David Yuile will leave AAPT at the end of February. The CEO, who joined AAPT in 2011, will depart the telco the same day as Telecom's $450 million sale of the company to TPG is due to be finalised.
"David and his management team have done an outstanding job during the last three years to simplify, stabilise and reshape the company," Telecom chief Simon Moutter said.
"With AAPT now performing very well and joining the TPG group, David departs with our thanks and best wishes."
A Telecom statement described the sale of AAPT to TPG as the culmination of a transformation driven by Yuile during his time at the helm of the company.
"I am incredibly proud of what we have achieved at AAPT, transforming the company into a highly competitive data and internet provider," Yuile said in a statement. Yuile said it was the right time for him to "consider new options".
Telecom's sale of AAPT to TPG was announced in September last year. In 2010 iiNet purchased AAPT's consumer division from Telecom.