Code Geass has been adapted into a manga series by publisher Kadokawa Shoten. Several other series serving as sidestories, each containing an alternate timeline, have also been published. The first four of the manga series have been licensed for an English language release in North America by Bandai Entertainment.
- Code Geass: Lelouch of the Rebellion is a manga adaptation of the television series. It is written by Majiko~! and originally serialized Monthly Asuka. Focusing on the protagonist of the series, Lelouch Lamperouge, the series maintains the anime's basic storyline, though some events and characters have changed. Its chapters were collected in eight tankōbon volumes released from December 26, 2006 to March 26, 2010. Bandai's English adaptation of the series was published from July 29, 2008 to February 15, 2011.
- Code Geass: Suzaku of the Counterattack (コードギアス 反攻のスザク Kōdo Giasu: Hankō no Suzaku) focuses on the character Suzaku Kururugi in an alternate reality, where he fights against the criminal organization known as the Black Knights. The series was written by Atsuro Yomino and serialized in Beans A magazine. It was released in two volumes on June 26, 2007 and September 26, 2008. The first English volume was released on January 6, 2009, and the second followed it on October 13, 2009.
- Code Geass: Nightmare of Nunnally (コードギアス ナイトメア・オブ・ナナリー Kōdo Giasu Naitomea Obu Nanarī) was serialized in Comp Ace and written by Tomomasa Takuma. It focuses on Lelouch's sister, Nunnally Lamperouge, who goes to search her missing brother when her health is restored by an entity named Nemo. It was published in five volumes from June 26, 2007 to April 25, 2009. The English volumes were published from June 9, 2009 to March 23, 2010.
- Code Geass: Tales of an Alternate Shogunate (幕末異聞録 コードギアス 反逆のルルーシュ Bakumatsu Ibun Roku Kōdo Giasu Hangyaku no Rurūshu), was serialized in Kerokero Ace. Set in an alternate 1853, Lelouch is the commander of the Shogunate's military counterinsurgence brigade known as the Shinsengumi, which fights the Black Revolutionaries, a rebel group led by a masked individual known as Rei. It was released on a single volume on October 25, 2010, while the English version was published on May 10, 2011.
- Code Geass: Renya of Darkness (コードギアス 漆黒の連夜 Kōdo Giasu: Shikkoku no Renya) is a manga series originally greenlit by Bandai for 2010, with the anime director Goro Taniguchi is scripting the story. The story is set in official Code Geass history as the anime, but takes place during Japan's historical Edo era. The series follows Renya, a 17-year-old boy who encounters a mysterious, perpetually young witch named "Reifū C.C." seeking a new partner for a covenant. It began publication in the May 2010 issue of Shōnen Ace. Bandai Entertainment had licensed the manga for publication in English, as with the other adaptations, but these plans were officially cancelled in January of 2012.
- Code Geass: Oz the Reflection (コードギアス 双貌のオズ Kōdo Giasu: Sōbō no Ozu) is a multimedia spin-off featuring two different protagonists; the project includes a manga series published in Newtype Ace. Set between the first and second series of the anime, the manga features Oldrin Zevon, a Knightmare Frame pilot who serves as a member of the Glinda Knights, the Britannian Empire's anti-terrorism unit.