The 10-time grand prix winner was overlooked for a new deal with the Swiss squad in favour of F2 championship leader Gabriel Bortoleto.
The Brazilian will join Nico Hulkenberg on a two-year deal, the pairing remaining with the operation as it becomes Audi for 2026.
That has left Bottas on the sidelines for next season though looking for an F1 return the year after.
His fate was always uncertain, and the longer it dragged on the less likely it seemed that Sauber would opt for his experience.
“The closer we’re getting to that date, I did definitely figure out that there was other drivers as candidates as well,” Bottas said of how his fate played out.
“And of course, you start to hear rumours.
“In the end, I still thought it’s maybe 50:50 chance.
“I got the call on Monday. But yeah, at least I know now. I just need to figure out what’s next.
“There’s lots of exciting things ahead,” he added.
“I’m fine with it. It’s a tricky sport.
“I think I got into a bit unlucky situation, in terms of hanging on to the last seat on the grid, and when that doesn’t happen, then obviously you’re out for now.”
It’s thought a reserve role at Mercedes is the most likely destination for the 35-year-old.
Bottas spent five years with the squad from 2017 and he remains highly respected at Brackley for his contribution during the squad’s years dominating the sport.
But should a race drive not materialise on the other side of that, it’s likely a career beyond F1 will beckon.
“The way my active F1 driving career ended for now, it wasn’t the best way that you can’t really decide yourself,” Bottas confessed.
“I feel like still I have lots to give for the sport and I still love it. I love the racing against the best drivers in the world, in the best cars in the world. That’s what I love.
“So I’m just trying to figure out now what is the next move.
“I don’t really have that much more. I’m taking it day by day. There’s some interesting stuff on the table and then we’ll see.
“At the moment, I feel like jumping into a new category comes quite quick,” he added.
“We’re almost in December, so I think that would be more realistic that if I didn’t find a seat in F1 during ‘25 or for ‘26, then probably would be from ‘26.
“But it’s all these things that I need to kind of try and plan. But the picture is starting to form in my head what is the ideal situation.”
Bottas has previously confirmed to Speedcafe that he will race a Supercar at some point.
He’s already had experience behind the wheel at the Adelaide Motorsport Festival.
The 2025 Supercars grid is complete, though a number of co-driving opportunities exist, including at a number of high-profile teams.
Next year’s Enduro Cup includes The Bend and the Bathurst 1000, the two events separated by a month.
Bottas is a regular to Adelaide courtesy of his partner, Tiffany Cromwell, and has expressed an interest in competing at Bathurst.
Neither event clashes with F1’s 2025 schedule, with The Bend slotting in between the Italian and Azerbaijan Grands Prix, and the 1000 between races in Singapore and the United States.
