The 37-year-old has been a Supercars regular since 2002, starting out with Holden's Young Lions programme and the Walkinshaw-run K-Mart Racing Team, before he and brother Todd set up the standalone Kelly Racing squad in 2009.
He's been a KR driver ever since, racing Holdens, factory-backed Nissans and, as of this year, a Ford Mustang along the way.
During his full-time career Kelly has racked up two Bathurst 1000 victories, 13 race wins in total, 57 podiums and was crowned the 2006 Supercars champion.
“While the 2020 season draws to a close so does my full-time Supercars driving career," said Kelly.
"Firstly, I have really loved the opportunity to drive the Castrol-backed Ford Mustang in its first year with Kelly Racing. There were many challenges put forward in 2020 with COVID and the Mustang programme in its infancy at Kelly Racing, which both have made on track results tough at times.
"It hasn’t been the fairy-tale ending that I would love to have gone out with, but I have to step off the merry-go-round at some point and I personally feel that the right time is now.
“Whilst as a driver you always want to win, and externally your on-track results hold the biggest influence on your report card, and as you’d expect from any athlete, I’ll leave wanting more.
"But one thing’s for sure, I will step away satisfied with having always having given my best and never giving in, no matter how far back we were.
“I have had a solid hustle over the past 20 years in motorsport, never really sitting still. So as far as what the future holds for me personally, as I step away from Kelly Racing, I’ll firstly take some time to reflect on my decision and then go about planning a solid attack on the next chapter of my life, whatever that might be.”
Todd Kelly added: “Well done to Rick on an outstanding career. He has had a big impact on the sport during his time as a driver and has not only had success on the track but been a leader in both fan and sponsor engagement.
“Rick has also been a fantastic mentor to Andre [Heimgartner] and other young drivers with his approach to his role as a driver.
"It’s going to be quite different not having Rick driving full time, however everyone at Kelly Racing wishes Rick all the best with his future and congratulates him on a successful career in Supercars.”
The announcement specifically references a step back from "full-time Supercars driving commitments", leaving the door well ajar for Kelly to slot into an endurance role at either KR or elsewhere.
As for KR seat, there are a number of potential suitors as a turbulent silly season continues to play out.
Race winner Fabian Coulthard is now on the market after being told he won't be part of the new-look Dick Johnson Racing outfit, which is expected to field cars for Anton De Pasquale and Will Davison.
Brodie Kostecki is another driver looking for a main game drive, while the potential wildcard to the silly season is David Reynolds, whose future at Erebus Motorsport is subject to much speculation – despite his 10-year deal with the squad.
Both Coulthard and Reynolds have also been linked to Brad Jones Racing, which will require a restructure due to the Blanchard family-owned Racing Entitlement Contract, which had been underpinning Macauley Jones' entry, on the move.