The 2020 Tour Down Under winner will represent the Australian national team in Adelaide for the first time since making his debut in 2008.
Porte's opposition will feature domestic teams and notable names eager to test themselves in a National Road Series stage race.
Riders will find themselves on familiar terrain during the event, with Stage 3 finishing on Willunga Hill before concluding with criteriums around Victoria Park the next day.
Race Director Stuart O'Grady was delighted with Porte's inclusion in the event, fresh from his incredible podium finish at the Tour de France.
"It’s fantastic that Richie and his family are back in Australia after an incredible year," O'Grady said.
"For all the cycling fans out there and the public to be able to congratulate Richie in person for his historic podium in the TDF is just amazing.
"Being in Adelaide and supporting this event means a lot to the Santos Tour Down Under team behind the race and gives the young up and coming riders an amazing opportunity to ride alongside one of this country’s greatest cyclists."
The 35-year-old, now a member of Team Ineos-Grenadiers for the 2021 season, is currently in quarantine in Perth and is expected to travel back to Tasmania for both the holidays and his pre-season training.
"There is plenty to love about Adelaide in January and it will be nice to catch up with the Aussie cycling fans to say hi," Porte added.
"I think it’s good the South Australian government has got behind it too."
