This timeline shows the dates (and order of release) of all of the various media relating to Douglas Adams' The Hitchhiker's Guide to the Galaxy series. Where multiple releases/broadcasts occurred, the first one is given.
| Date | Medium | Title | |
|---|---|---|---|
| March 8 – April 12, 1978 | Radio series | Primary Phase: "Fit the First" to "Fit the Sixth" | |
| December 24, 1978 | Radio series | Christmas Special, which became Secondary Phase: "Fit the Seventh" | |
| May 1–9, 1979 | Stage show | The Hitchhiker's Guide to the Galaxy (ICA) | |
| 1979 | Record | The Hitchhiker's Guide to the Galaxy | |
| October 1979 | Novel | The Hitchhiker's Guide to the Galaxy | |
| January 21–25, 1980 | Radio series | Secondary Phase: "Fit the Eighth" to "Fit the Twelfth" | |
| January 15 – February 23, 1980 | Stage show | The Hitchhiker's Guide to the Galaxy (Theatr Clwyd) | |
| 1980 | Record | The Hitchhiker's Guide to the Galaxy Part Two: The Restaurant at the End of the Universe | |
| October, 1980 | Novel | The Restaurant at the End of the Universe | |
| July 13 – August 2 [1] 1980 | Stage show | The Hitchhiker's Guide to the Galaxy (Rainbow) | |
| January 5 – February 9, 1981 | TV series | The Hitchhiker's Guide to the Galaxy | |
| 1982 | Novel | Life, the Universe and Everything | |
| October 1984 | Computer game | The Hitchhiker's Guide to the Galaxy | |
| November 1984 | Novel | So Long, and Thanks for All the Fish | |
| 1985 | Radio scripts | The Hitchhiker's Guide to the Galaxy: The Original Radio Scripts | |
| 1986 | Short story | "Young Zaphod Plays It Safe" | |
| 1992 | Novel | Mostly Harmless | |
| May 11, 2001 | Death of Douglas Adams | ||
| September 21 – October 26, 2004 | Radio series | Tertiary Phase: "Fit the Thirteenth" to "Fit the Eighteenth" | |
| April 28, 2005 | Film | The Hitchhiker's Guide to the Galaxy | |
| May 3–24, 2005 | Radio series | Quandary Phase: "Fit the Nineteenth" to "Fit the Twenty-Second" | |
| May 31 – June 21, 2005 | Radio series | Quintessential Phase: "Fit the Twenty-Third" to "Fit the Twenty-Sixth" | |
| March 12, [2] 2008 | Stage show | Live reading of Fit the Second (by the original cast) at the 6th Douglas Adams Memorial Lecture. | |
| October 11, [3] 2009 | Stage show | Hitchhikers Live On Stage! at Hitchcon event for publication of sixth book (below). | |
| October 12, 2009 | Novel | And Another Thing... , by Eoin Colfer | |
| June 8 – July 21, 2012 | Stage show | The Hitchhiker's Guide to the Galaxy Radio Show Live | |
| September 14 – October 20, 2013 | Stage show | The Hitchhiker's Guide to the Galaxy Radio Show Live (Planned to run to November 30, the show closed early.) | |
| March 29, 2014 | Radio show | The Hitchhiker's Guide to the Galaxy , a live radio broadcast in front of an audience as part of Radio 4's Character Invasion Day | |
| March 8 – April 12, 2018 | Radio series | Hexagonal Phase: "Fit the Twenty-Seventh" to "Fit the Thirty-Second" | |
| November 15 2025 – February 15 2026 | Stage show | The Hitchhiker's Guide to the Galaxy Live Immersive Show (Riverside) | |