His maiden season with the team was highlighted by a second place at Hidden Valley in August.
The 2010 champion finished 13th in the 2020 standings, and registered 13 top 10 finishes in 25 starts.
On Tuesday, Tickford unveiled renders of Courtney's 2021 scheme, with Boost Mobile returning to back the #44 Ford Mustang.
"I'm really looking forward to the 2021 season, especially with the slick new look on the Boost Mobile Mustang," the 40-year-old said.
"Even with all the craziness of last year I really enjoyed getting to know everyone at Tickford, and getting to raise a trophy again at Darwin was really special.
"Having a full off-season to properly prepare gives me a lot of confidence heading into 2021."
That could pay dividends for Courtney as he bids to return to the front of the grid.
"Not having to worry about learning the car or getting familiar with the team, just a full focus on achieving results, which is really exciting," he said.
"I can't wait to hit the track with the Boost Mobile Racing crew and hopefully score some more silverware."
Courtney will make his competitive return at the Repco Mt Panorama 500 across February 26-28. Tickets are on sale now.