The 44-year-old actor and 31-year-old actress attended the movie's Los Angeles premiere at the TCL Chinese Theatre in Hollywood.
Affleck looked dapper in a blue three-piece suit and patterned tie, while Kendrick wore a black, off-shoulder dress cinched with several belts. The actress accessorized with bar stud earrings and strappy pumps.
The Accountant was written by Bill Dubuque (The Judge) and directed by Gavin O'Connor (Warrior). The movie centers on a mathematics savant (Affleck) who serves as a forensic accountant for dangerous criminal organizations.
"[It] was something like putting on an expressionless mask. It was a real challenge, but also an honor to play him. I hadn't read an autistic character in a film script like this," Affleck recently told the Chicago Sun-Times.
"[It] was nice to play a guy who isn't a superhero," the Batman actor added. "He's capable of exceptional things -- but within the realm of human possibility and human physicality."
The Accountant opens in theaters Friday. Affleck is also slated to reprise Batman in Justice League and The Batman, while Kendrick will star in Table 19 with Lisa Kudrow.