Bianchi joined Marussia just a week prior to the start of the current campaign after sponsorship issues prevented the man the team initially hired in Luiz Razia from taking up the seat.
The Frenchman has since performed admirably, finishing a high of 13th in Malaysia, and has out-qualified Chilton in all 13 races this season.
It is for that reason Chilton has not yet been offered a place for next year as he still has a lot to prove, starting with this weekend's Korean Grand Prix, and will likely have to wait until the end of the campaign to learn his fate.
Team principal John Booth said: "It gives us great pleasure to announce we will go forward into 2014 with Jules as one of our race drivers.
"Jules joined us at very short notice at the end of pre-season testing, with only two days of running under his belt.
"He rose to the challenge of his debut season exceptionally well and since that time has clearly demonstrated his ability and potential.
"2014 heralds a new era for the sport and continuity and consistency of line-up will be important in helping us to navigate the transition.
"We look forward to confirming our full race driver line-up later in the season.
"Until then we have an important job to do to ensure we retain our 10th place in the constructors' championship and this is where our full focus will lie in the intervening period."
With an eye on next season, Bianchi said: "I couldn't have wished for a more supportive environment in which to make my F1 debut and from the very beginning I have always felt completely at home with the team.
"We started the season very well and while the challenge has increased as the season has developed, we have learned important lessons together that will place us in a much stronger position next year when there are a lot of changes for the sport and the team to get used to.
"I am very excited to be part of the team as we all enter this new era of F1 and I look forward to achieving some rewarding performances together."