The first season of How I Met Your Mother premiered on CBS on September 19, 2005, and concluded on May 15, 2006, consisting of 22 episodes. It is set in 2005 and follows Ted Mosby, a 27-year-old architect living in Manhattan with his two best friends from college: Marshall Eriksen, a law student, and Lily Aldrin, a kindergarten teacher. The story begins when Marshall proposes to Lily after nearly nine years of dating, prompting Ted to start searching for his soulmate. Ted soon meets Robin Scherbatsky, an ambitious Canadian reporter, and quickly falls in love with her, although she does not want a serious relationship initially

. The season is framed by scenes set in 2030, where an older Ted (voiced by Bob Saget) tells his children the story of how he met their mother. Throughout the season, Ted's romantic pursuits, his friendship dynamics with Barney Stinson—a self-appointed best friend and serial womanizer—and the evolving relationships among the group are explored. Key plot points include Ted's efforts to find the mysterious woman he met at a wedding, Robin confronting her feelings for Ted, and Lily taking an art fellowship in San Francisco, which strains her relationship with Marshall

. The first season received mixed-to-positive reviews and averaged 9.47 million viewers per episode in the U.S., ranking 51st among primetime shows during the 2005–2006 television season