The Big Bang Theory: How Many Episodes Are There In Total?

CBS struck gold with "The Big Bang Theory," a sitcom about a group of Caltech scientists who are capable of understanding the most complicated academic theories but who lack the social and emotional intelligence to back up their brain power. After they were first introduced, Sheldon Cooper (Jim Parsons) and his friends managed to charm audiences enough to bring in big viewing numbers and remain on the air for over a decade. By the time the show ended, "The Big Bang Theory" had aired an impressive 279 episodes, which were released over the course of 12 seasons between September 24, 2007 and May 16, 2019.

Created by Bill Prady and sitcom legend Chuck Lorre, "The Big Bang Theory" became one of the most popular sitcoms during the modern golden age of television. A network show that managed to hang on for roughly 12 years and thrive despite the surging popularity of streaming services during its run, "The Big Bang Theory" represents one of the last examples of appointment TV as audiences used to experience it. And despite launching less than two months before the 2007 Writers Guild strike, the show persevered and avoided an early cancellation.

The pilot episode of "The Big Bang Theory" introduced physicists Leonard Hofstadter (Johnny Galecki) and Sheldon Cooper, who struggle to contain themselves when they learn an attractive blonde woman named Penny (Kaley Cuoco) has moved into their building. Season 1 featured 17 episodes, and by the 2nd and 3rd seasons, the show had expanded to 23 episodes. From Season 4 onward, the series was extended to include 24 episodes per season. The series ends with a two-part finale, which sees Sheldon and his wife Amy (Mayim Bialik) win the Nobel Prize. Meanwhile, Leonard and Penny share that they are expecting their first baby.

"The Big Bang Theory" was certainly successful enough to be renewed for a 13th season, but that never ended up happening. According to the book "The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series" (as reported by BuzzFeed), Jim Parsons made the decision not to proceed with the series after the show's 12th season, and in turn, the producers decided the show could not continue without Parsons. He was eager to move on to different career opportunities, but his decision resulted in some tension among the cast members — especially co-stars Cuoco and Galecki. Ultimately, the cast decided to put those feelings aside to get as much as they could out of their final season together.