1975

History of the Doctor Who Universe

 * Events of DW: The Web of Fear (Note: This is the dating suggested in the actual story, though it contradicts the dating suggested for other UNIT era stories, and is itself contradicted by "Downtime." See UNIT dating controversy and "No Future" for further explanation.)
 * On Earth, the introduction of the Betamax videotape recording system officially launches the home video era, although the VHS tape, released in 1976, would ultimately become the dominant home video format for the next 25 years. Among those interested in the new industry is time-displaced Billy Shipton who, acting on instructions received from the Doctor years earlier, enters into the video publishing industry in preparation for his ultimate involvement in DVD authoring decades later. (DW: Blink)
 * Toshiko Sato is born.

January to April

 * The stage play SP: Doctor Who and the Daleks in The Seven Keys to Doomsday tours the UK.

January

 * DWN: Doctor Who and the Curse of Peladon is first published.
 * 4 - DW: Robot Episode 2 is first broadcast.
 * 11 - DW: Robot Episode 3 is first broadcast.
 * 16 - The BBC's Audience Research Dept. files an Audience Research Report on DW: Robot Episode 1. The episode rates a Reaction Index of 53. Reaction to new Doctor Tom Baker is mixed, with some respondants saying he would take some getting used to.
 * 18 - DW: Robot Episode 4 is first broadcast. Although there would be two more UNIT stories over the next year, this episode marked the end of the Doctor's continued involvement with UNIT.
 * 25 - DW: The Ark in Space Episode 1 is first broadcast.

February

 * 01 - DW: The Ark in Space Episode 2 is first broadcast.
 * 08 - DW: The Ark in Space Episode 3 is first broadcast.
 * 15 - DW: The Ark in Space Episode 4 is first broadcast.
 * 20 - DWN: Doctor Who and the Cybermen is first published.
 * 22 - DW: The Sontaran Experiment Episode 1 is first broadcast.

March

 * 01 - DW: The Sontaran Experiment Episode 2 is first broadcast.
 * 08 - DW: Genesis of the Daleks Episode 1 is first broadcast. First appearance of Davros.
 * 10 - Yee Jee Tso, who portrayed Chang Lee in the 1996 Doctor Who television movie, is born.
 * 13 - DWN: Doctor Who and the Giant Robot is first published. First novelisation of a Fourth Doctor serial and the first novelisation to be published during the same TV season in which the adapted serial (DW: Robot) was actually broadcast.
 * 15 - DW: Genesis of the Daleks Episode 2 is first broadcast.
 * 22 - DW: Genesis of the Daleks Episode 3 is first broadcast.
 * 29 - DW: Genesis of the Daleks Episode 4 is first broadcast.

April

 * 05 - DW: Genesis of the Daleks Episode 5 is first broadcast.
 * 12 - DW: Genesis of the Daleks Episode 6 is first broadcast.
 * 19 - DW: Revenge of the Cybermen Episode 1 is first broadcast.
 * 23 - William Hartnell, the first actor to portray the Doctor, dies at Marden, Kent, England. Hartnell has the sad distinction of being the first major, ongoing cast member of Doctor Who to pass away.
 * 26 - DW: Revenge of the Cybermen Episode 2 is first broadcast.

May

 * 03 - DW: Revenge of the Cybermen Episode 3 is first broadcast.
 * 10 - DW: Revenge of the Cybermen Episode 4 is first broadcast, bringing Season 12 to a premature end following the BBC's decision to reschedule the originally planned season finale, DW: Terror of the Zygons, to the start of Season 13.
 * 15 - DWN: Doctor Who and the Terror of the Autons is first published.

July

 * 15 - Raf De La Torre, who played the Senior Judge in DW: The Keys of Marinus, dies.

August

 * 21 - DWN: Doctor Who and the Green Death is first published.
 * 23 - Tom Baker presents Disney Time in character as the Fourth Doctor
 * 30 - DW: Terror of the Zygons Episode 1 is first broadcast, opening Season 13 and marking the first autumn start for a Doctor Who season since 1968-69. The serial was originally intended to end Season 12, but was pushed back to make a fall season start feasible.

September

 * Doctor Who Annual 1976 published.
 * Terry Nation's Dalek Annual 1976 published
 * 06 - DW: Terror of the Zygons Episode 2 is first broadcast.
 * 13 - DW: Terror of the Zygons Episode 3 is first broadcast.
 * 20 - DW: Terror of the Zygons Episode 4 is first broadcast. Ian Marter leaves the series as a regular with this episode, although he will return a few weeks later in DW: The Android Invasion in a guest appearance. This is also Nicholas Courtney's final regular appearance as Brigadier Alistair Gordon Lethbridge-Stewart; he will next play the character in the 1983 serial DW: Mawdryn Undead. Although UNIT returns in The Android Invasion, and the Doctor is on a UNIT mission in DW: The Seeds of Doom, this being the last appearance of the Brigadier marks this as officially the end of the UNIT era.
 * 27 - DW: Planet of Evil Episode 1 is first broadcast.

October

 * 04 - DW: Planet of Evil Episode 2 is first broadcast.
 * 11 - DW: Planet of Evil Episode 3 is first broadcast.
 * 16 - DWN: Doctor Who and the Planet of the Spiders is first published.
 * 18 - DW: Planet of Evil Episode 4 is first broadcast.
 * 25 - DW: Pyramids of Mars Episode 1 is first broadcast.

November

 * 01 - DW: Pyramids of Mars Episode 2 is first broadcast.
 * 08 - DW: Pyramids of Mars Episode 3 is first broadcast.
 * 15 - DW: Pyramids of Mars Episode 4 is first broadcast.
 * 20 - DWN: Doctor Who - The Three Doctors is first published. First novelisation not to use the title form Doctor Who and the .... This is also the first Target Books-commissioned novelisation to feature the First Doctor.
 * The Doctor Who Monster Book is first published.
 * 22 - DW: The Android Invasion Episode 1 is first broadcast.
 * 29 - DW: The Android Invasion Episode 2 is first broadcast.

December

 * 06 - DW: The Android Invasion Episode 3 is first broadcast.
 * Noel Clarke, who plays Mickey Smith in the revived Doctor Who, is born.
 * 13 - DW: The Android Invasion Episode 4 is first broadcast. Final appearances of Ian Marter as Harry Sullivan, John Levene as  John Benton and, as a regular part of the series, UNIT. After this episode the series goes on a brief hiatus for Christmas.

Unknown

 * Anna-Louise Plowman, the actor who played Diana Goddard in DW: Dalek, is born.