Stewart is leaving Joe Gibbs Racing after this season, which he will complete driving the No. 20 Toyota.
His Stewart-Haas Racing team is to begin competition next year. Stewart said he will take No. 14 and have Office Depot and Old Spice as the main sponsors of the red and black Chevrolet. Office Depot will sponsor Stewart's car in 60 percent of the races with Old Spice taking the rest.
The other car in the Stewart-Haas stable will carry the No. 4. A driver hasn't been hired for that car.
"Four was my first-ever go-kart number that I started with," Stewart said. "Everybody knows that A.J. Foyt has always been my all-time favorite hero. And when this opportunity came about, it was about a five-minute tug-of-war between do I want my first number back or do I want A.J.'s number and it was pretty easy to decide that I wanted the number that my all-time hero had."