How Many Series Of The Big Bang Theory Are There Better -

| Series | Episodes | Original Run (US) | Key Storylines | |--------|----------|-------------------|----------------| | | 17 | Sept 2007 – May 2008 | Introduction of Leonard, Sheldon, Penny. The “roommate agreement.” Sheldon’s spot on the couch. | | 2 | 23 | Sept 2008 – May 2009 | Introduction of Leslie Winkle (recurring). Leonard & Penny’s first kiss. Sheldon’s rival Barry Kripke. | | 3 | 23 | Sept 2009 – May 2010 | Howard & Bernadette meet. Sheldon & Leonard’s “truce.” Penny cuts her hair (major fan reaction). | | 4 | 24 | Sept 2010 – May 2011 | Amy Farrah Fowler and Bernadette become regulars. Priya (Leonard’s sister) arrives. | | 5 | 24 | Sept 2011 – May 2012 | Howard goes to space. Leonard & Penny break up again. Sheldon & Amy’s first date. | | 6 | 24 | Sept 2012 – May 2013 | Howard returns from space. Raj’s selective mutism improves. Penny gets a real job (sales at Bernadette’s company). | | 7 | 24 | Sept 2013 – May 2014 | Sheldon breaks Amy’s heart. Leonard goes on North Sea expedition. Howard’s mother (voiced by Carol Ann Susi) dies off-screen. | | 8 | 24 | Sept 2014 – May 2015 | Sheldon and Leonard’s friendship fractures over a failed experiment. Penny & Leonard marry in Las Vegas. | | 9 | 24 | Sept 2015 – May 2016 | Sheldon & Amy reunite. Howard & Bernadette’s first child (Halley). Raj dates Emily. | | 10 | 24 | Sept 2016 – May 2017 | Sheldon proposes to Amy. Howard’s second child (Neil Michael). Leonard’s father appears. | | 11 | 24 | Sept 2017 – May 2018 | Sheldon & Amy’s wedding. Introduction of Sheldon’s brother (Jerry O’Connell). | | 12 | 24 | Sept 2018 – May 2019 | Sheldon & Amy win the Nobel Prize. The elevator is fixed (series finale). |

The Big Bang Theory (often abbreviated TBBT) is one of the most successful sitcoms of the 21st century. Created by Chuck Lorre and Bill Prady, it premiered on CBS in 2007 and ran for 12 seasons (known as "series" in UK/Commonwealth English) before concluding in 2019. how many series of the big bang theory are there

If someone tells you there are 13 series, they are either confusing a spin-off, counting the failed pilot, or referring to a regional broadcast split. The definitive, creator-approved answer is: | Series | Episodes | Original Run (US)