As previously reported by Motorsport.com, Symonds was set to leave his position as F1's chief technical officer after seven years in the job, playing a crucial role in contributing to F1's technical regulations for 2022 and 2026.
With the chassis rules for 2026 all but finalised, Symonds decided to leave the organisation as had long been under consideration.
It has now emerged that Andretti Global is Symonds's next destination, with Michael Andretti's organisation hiring the 70-year-old as an Executive Engineering Consultant.
He will work from the team's recently opened UK base in Silverstone following a gardening leave period.
"We couldn't be more excited to welcome Pat to the Andretti family," said Andretti. "Pat's keen understanding of aerodynamics, vehicle dynamics and Formula 1 power units will be instrumental as we continue to build a competitive team.
"I believe his expertise has been pivotal in shaping the narrative of Formula 1 and his vote of confidence in joining our effort speaks volumes. I'm really happy with this next step as our work continues at pace."
At Andretti Symonds re-joins former Benetton and Renault colleague Nick Chester, who heads up the engineering team as Andretti Cadillac's technical director.
"I have had the pleasure to work with Pat in the past and he has a wealth of knowledge we can draw upon," said Chester.
"Pat will bring expertise across technical areas and team operations in his role as Executive Engineering Consultant that will help us develop the team."
Landing Symonds is another string to Andretti's bow as the American racing powerhouse aggressively pursues an F1 entry with GM brand Cadillac.
While it was denied entry for 2026, it has not taken no for an answer and continued its preparation, opening the Silverstone headquarters and starting a recruitment drive, with Symonds now emerging as the first major coup.
F1 has left the door open for a new attempt in 2028 with bespoke GM power units.
Symonds was an integral part of the Benetton team that took championships with Michael Schumacher in the mid-90s.
He stayed with the team through its Renault guise until leaving in the wake of the 2008 Singapore Crashgate scandal, before returning to the series as a consultant for Virgin. He then became CTO at Williams and joined the F1 organisation in 2017.
F1's refusal to accept Andretti's bid to join as an 11th team has ruffled some feathers in the States.
Last month Mario Andretti made an appearance on Capitol Hill as several Congress members wrote to F1 and its American owner Liberty Media to demand answers on why Andretti's bid was rejected, invoking antitrust laws.
It has since emerged that several senators have asked the Department of Justice and the Federal Trade Commission to commence a formal investigation.
The House's Judiciary Committee has already launched its own probe into the matter.