Ranbir Kapoor was the original choice for the lead role. Director Ayan Mukerji wrote the film keeping him in his mind.
Like Ranbir, Konkona Sen Sharma was the original choice for the role of Aisha Banerjee.In an interview with a TV channel, Ranbir said that Ayan had already thought about casting Konkana in the film but he didn't tell that to him.After the narration of the script, Ranbir coincidentally recommended Konkona's name to Ayan mainly because she suited the character and no other actress from his generation could have done the role.Ayan Mukherji took around one and a half years to write the story and screenplay of the movie.Ayan then narrated the script to Karan Johar who approved the script in one narration and decided to produce it.The song 'Iktara' was not originally used in the soundtrack. Ranbir loved the song in the background and he wanted to use the song officially in some other movie, if it is not used here.However, later the song, Iktara, was used in two different versions - Female and Male that were picturized on Konkona and Ranbir respectively.The film got delayed by 3 months when Ranbir Kapoor grew a beard for a role in Rocket Singh: Salesman of the Year (2009), therefore, he was unavailable to shoot some of the patchworks.Ranbir Kapoor tried some 65-70 boxers for the introducing shot in Wake Up Sid. And all the boxers that he wore in the film were his personal boxers.Anupam Kher plays father to Ranbir Kapoor in this film. He had played grandfather to Ranbir's real-life father Rishi Kapoor in the 1988 Yash Chopra film, Vijay.Though the subtitles say 'Bombay,' this film takes place in 2008, and the city was officially renamed as 'Mumbai' in November 1995.Debut of Shikha Talsania.Karan Johar (producer) considered Imran Khan for the role of Sid.According to Ayan Mukerji, the scene where Sid and Aisha meet for the first time at Debbie's party had to be re-shot.Ayan Mukerji and Ranbir Kapoor are best friends in real lifeAyan Mukherjee's directorial debut.Ayan Mukerji and Ranbir Kapoor are best friends in real life.In a scene where Ranbir Kapoor finds his mother looking through his photo album, they are actual Ranbir's childhood photographs.The movie was entirely shot in Mumbai, covering the South and Bandra areas.The college sequence was shot at H.R. College of Commerce and Economics near Churchgate.Maharashtra Navnirman Sena supporters protested to halt the screening of Wake Up Sid in Mumbai and Pune. The MNS objected the use of the word 'Bombay' instead of 'Mumbai' in the movie.Maharashtra Navnirman Sena supporters protested to halt the screening of Wake Up Sid in Mumbai and Pune. The MNS objected the use of the word 'Bombay' instead of 'Mumbai' in the movie.Both the leads won rave reviews for their performances, and Kapoor received awards and nominations for his acting.The film's dialogues were written by Niranjan Iyengar.The soundtrack has music composed by Shankar-Ehsaan-Loy with lyrics by Javed AkhtarOne song in the film has been composed by Amit Trivedi who scored the background music for the film.Do Knot Disturb also released during the same time, but Wake Up Sid got a larger portion of the audience.The film was made at a budget of 24 crores.It made 84 crores at the box office.