Luiz Razia, who was initially confirmed as replacement for Timo Glock last month, has had his contract terminated by the Banbury-based team with immediate effect.
Team principal John Booth said: "Having made clear the basis on which we must operate in 2013, and given the steps we had taken to put that new structure in place, we had no alternative but to remain true to the principles which we had identified as being key to securing our long-term future."
Razia initially drove for Marussia for two days in the opening pre-season test in Jerez.
However, the 21-year-old, who was last season's GP2 series runner-up, was withdrawn from last week's second test due to what was understood to be difficulties with his sponsors.
With the clock ticking ahead of the season-opening race in Australia, with practice in a fortnight's time, Marussia were forced to act.
Only Thursday, Bianchi, who spent last year as Force India's reserve driver, discovered he had missed out on promotion to the full-time race seat as the team instead turned to Adrian Sutil.
Just over 24 hours later, 23-year-old Frenchman Bianchi, a member of Ferrari's young driver academy, finds himself finally in F1.
Bianchi said: "I am thrilled to have secured a race seat with Marussia.
"Racing in Formula One this season has been my goal over the winter, and after evaluating a number of options I am very excited to have this opportunity to demonstrate I am ready for this next step in my racing career.
"I am also very grateful to the Ferrari academy that has always supported me and given me the possibility to mature as a racing driver, enabling me to be fully prepared for this new exciting challenge.
"The next two weeks of preparation for the season will be incredibly busy, but I am ready to get started tomorrow with my first day in the car."
Earlier on Saturday Razia said he was doing all he could to guarantee his seat with Marussia for the forthcoming season.
Razia tweeted: "I'm doing absolutely everything possible to resolve the situation you all know about."
It is now clear it was not enough, much to Marussia's disappointment, although it could be said they have a much quicker, more accomplished driver in the second seat in Bianchi, albeit perhaps not providing as much funding as Razia had initially promised.
Booth added: "Jules is a proven talent who is highly regarded within the paddock.
"He has been on a clear trajectory towards Formula One and has achieved some impressive performances through the various feeder formulae.
"His obvious pedigree put him on the radar for a number of teams over the winter as a driver ready to step up to Formula One.
"Jules can now look forward to a very swift initiation into the team over the course of the next two days here in Barcelona."
Bianchi will be behind the wheel for a day and a half, with Chilton allowed another half day to get used to a new aero specification to be placed on the car from Saturday.