As Formula 1 awaits news on Red Bull and Toro Rosso, Toto Wolff says there is still time to get everything into place should Mercedes have to field a third car.
At present neither Red Bull Racing nor Toro Rosso have confirmed engine deals for next season as both teams, owned by Red Bull billionaire Dietrich Mateschitz, opted to end their Renault contracts a year early.
Ferrari have reportedly offered to supply Toro Rosso with engines but none of F1's current engine manufactures are keen to power Red Bull.
This has led to concerns that Red Bull could quit Formula 1, taking junior team Toro Rosso out of the mix as well.
Should that happen the 2016 grid would be down to 18 cars which means if another team falls by the wayside and the grid drops below 18 cars, Mercedes, Ferrari and McLaren are all contracted to race a third car.
Asked whether it was too late in the game to do that, Wolff told Autosport: "No. The question is about how to finance the additional car, but logistically, it is possible.
"We have crunched the numbers and I wouldn't want to quote them officially, but all the teams were asked to look at the numbers a while ago and it is all pretty similar, so financially viable."
The Mercedes motorsport chief also believes third cars would be good for Formula 1 as a whole as it would open the door for young drivers to race.
"It would enable the smaller teams to place drivers and raise revenue by having them in the car. It would give teams more TV exposure and more media coverage with having a third car.
"Also, it would give young drivers the chance of driving in a competitive car in a competitive environment, stepping up from junior categories. We haven't seen many young drivers getting into Formula 1 recently, apart from through the Red Bull programme.
"There are many boys out there who deserve to be in Formula 1, and this [third cars] would be a good solution, a good possibility of benchmarking them against the very best."
In fact in an ideal Formula 1 world, Wolff would welcome Red Bull and Toro Rosso staying in the sport and the teams still running three cars.
"It is important for the sport teams like Red Bull and Toro Rosso stay in Formula 1, not only to make up the numbers but because the brand is very important to Formula 1. But you're responsible for your destiny, each of us.
"If it were the case some high-level people in Red Bull decided to pull out, a contingency plan would be to have three cars, so I don't see a scenario of having 18 cars being realistic.
"Now whether it is with Red Bull or without, I would rather have third cars and a grid of 26 or 28 cars in Formula 1."