List of Christmas episodes in The Big Bang Theory

The Big Bang Theory is an American sitcom by Chuck Lorre and Bill Prady, which aired on CBS from 2007 to 2019 for 12 seasons. The show follows the lives of 4 socially awkward scientists - Leonard, Sheldon, Howard, and Rajesh - who excel in their fields but struggle with social interactions. Their world changes when Penny, an aspiring actress and waitress, moves in next door. She introduces them to new experiences and relationships.

The show is known for its witty humor, nerd culture references, and character development. With seasons, major characters like Amy Farrah Fowler and Bernadette Rostenkowski were introduced, who became love interests for Sheldon and Howard, respectively. Over the years, the show's main characters became household names. The show has won 11 Primetime Emmy Awards, 14 People's Choice Awards, a Golden Globe Award, etc. The Big Bang Theory features many Christmas-themed episodes over the years.

Season 2, Episode 11- The Bath Item Gift Hypothesis

This is the first Christmas episode of the show. In the episode, Leonard meets award-winning researcher and experimental physicist Dr. David Underhill. He is overjoyed to assist Underhill but envies him for being more handsome and successful than him. Soon, David started dating Penny, but their relationship ended quickly when Penny found nude photos of Underhill’s wife on his phone. Leonard realizes he made a mistake when he confronts her.

Meanwhile, Sheldon worries about what present he should give Penny for Christmas, as he has to match the level of the gift she will give him. To his surprise, Penny gives him one of the best gifts he ever received. She gave him a napkin used and autographed by Leonard Nimoy. Sheldon was happy that he now owned Leonard Nimoy’s DNA and gave Penny a gift basket and a rare Sheldon hug in return.

Season 3, Episode 11- The Maternal Congruence

In this episode, Leonard’s mother, Dr. Beverly Hofstadter, visits him for Christmas. Leonard had an awkward relationship with his mother and was not so delighted about her visit. On the contrary, Sheldon was happy about her visit as they gel well together. Penny was upset that Leonard didn’t tell her about his mother’s visit. Leonard’s mother reveals that she and his father are getting divorced. Leonard comes to know that Sheldon knows more about his parents' lives than him.

Leonard doesn’t tell his mother about his relationship with Penny. She and Penny go to the Cheesecake Factory bar to drink. They both get drunk and Penny tells her about her relationship with Leonard. When they get back, Beverly scolds Leonard for not telling her that he is dating Penny. They confront each other and Beverly hugs him.

Season 6, Episode 11- The Santa Simulation

In this episode, the boys and Stuart play Dungeons & Dragons and Leonard is the Dungeon master. He sets up a Christmas theme and players have to rescue Santa Claus from hungry ogres. Raj decides to join Penny, Amy, and Bernadette for girls' night as his character dies early. They decide to find a girl for Raj and he also gets an email address of a girl which turns out to be a fake one.

Raj gets upset, and he and Amy connect with each other over their failed love lives. Meanwhile, Sheldon paralyzes Howard and Stuart’s character in the game which leads to Santa being eaten by the ogres in the dungeon. Sheldon reveals that he did not like celebrating Christmas, as in his childhood, he made a wish to Santa Claus to revive his grandfather, Pop-Pop, but instead, he received a set of Lincoln Logs which traumatized him.

Season 7, Episode 11- The Cooper Extraction

In the episode, Sheldon visits his pregnant sister in Texas to help her with her home birth. But because of his self-absorbed and unsympathetic nature, he was not helpful to his sister at all. In a video call, they all talk about how their life would have been if they had never met him. Amy tells Sheldon that he should be there with his sister and newborn nephew. Raj notices that she has influenced Sheldon significantly and Leonard shows her that Sheldon has a photo of her as a screensaver. When Sheldon returns home, he tells Amy that he would have preferred her to be with him in Texas.

Season 8, Episode 11- The Clean Room Infiltration

In this episode, Raj tells everyone that he will not be able to host the Christmas dinner as his father is visiting him for Christmas and he is depressed because of his divorce. Amy decides to host the Christmas dinner instead. Everyone gets bored at her Victorian-era-themed Christmas dinner. Sheldon wants to give Amy a better Christmas gift than hers and asks Bernadette for help. He gives Amy a framed picture of himself with Santa, along with a personalized message. Amy loved his gift and, in return, gave him a box of cookies made from his MeeMaw's recipe.

Season 10, Episode 12- The Holiday Summation

This is the last Christmas-themed episode of the show. Sheldon and Amy visited his mother Mary for Christmas. Sheldon was upset with his mother as she confessed to him that she thought that he would never find a girlfriend. Sheldon reacted to this by getting his ear pierced. Meanwhile, Penny and Leonard struggle to chop the Christmas tree and bring it home and on the other hand, Bernadette and Howard struggle with their newborn baby. Their baby was not crying nonstop and was not sleeping. In the end, Bernadette finds a way to stop her crying - she climbs into her crib and sleeps next to her.

Also read: How many episodes in the Big Bang Theory?