1981

February

 * 28 - The Fourth Doctor and Adric landed the TARDIS by the side of a motorway to gain measurements of a police box. Air hostess Tegan Jovanka stumbled aboard the TARDIS on her way to work at London's Heathrow Airport. (TV: Logopolis)
 * The Fifth Doctor tried to return Tegan to her own time, but instead the TARDIS landed on Monarch's ship. (TV: Four to Doomsday)

March

 * 1 - Following a fall from the Pharos Project's dish, the Fourth Doctor regenerated into his fifth incarnation. (TV: Logopolis) The newly regenerated Doctor and his companions Adric, Nyssa and Tegan Jovanka escaped in the TARDIS. (TV: Castrovalva)

April

 * 7 - Cassandra Elizabeth Schofield, the mother of the Seventh Doctor's companion Hex, was born to Hilda Schofield in Royal Bolton Hospital. (AUDIO: Project: Destiny)

June

 * Peter Tracey was given a suspended sentence for breaking and entering. (TV: A Girl's Best Friend)

July

 * The Fifth Doctor attended a cricket match in Leeds...twice. (PROSE: Graham Dilley Saves the World)

September

 * A hailstorm struck Moreton Harwood. It lasted only thirteen seconds, but destroyed Commander Bill Pollock's crops. (TV: A Girl's Best Friend)

December

 * 1 - 14 - Sarah Jane Smith was out of the country working for Reuters. (TV: A Girl's Best Friend)


 * 6 - Lavinia Smith departed Moreton Harwood for a lecture tour in the United States. Before leaving, she arranged for a mysterious crate addressed to her niece, Sarah Jane Smith, to be left at Moreton Harwood. (TV: A Girl's Best Friend)


 * 10 - Lavinia Smith phoned her ward Brendan Richards to tell him that he would be spending Christmas with Sarah Jane. Brendan waited for Sarah to pick him up at Wellington College for over a week, unaware that she was out of the country. (TV: A Girl's Best Friend)


 * 18 - Sarah Jane Smith met Brendan Richards for the first time. Shortly afterwards, she opened the crate addressed to her in Lavinia's house and activated K9 Mark III, who had been left in her flat in Croydon by the Doctor in 1978. (TV: A Girl's Best Friend)


 * 20 - 21 - Brendan Richards was kidnapped by the Hecate Cult, who intended to use him as a human sacrifice. However, he was rescued by Sarah Jane Smith and K9 Mark III before this could happen. (TV: A Girl's Best Friend)


 * 25 - Sarah Jane Smith, Brendan Richards and K9 Mark III spent Christmas Day with Howard and Juno Baker as Sarah Jane's aunt Lavinia Smith was in the United States. (TV: A Girl's Best Friend)
 * 29 - Members of the Hecate Cult at Moreton Harwood were tried for attempted murder. (TV: A Girl's Best Friend)

Unknown dates

 * Anne Travers became the British Cabinet's chief scientific advisor, succeeding her University of Cambridge lecturer and mentor Professor Rachel Jensen. She served in that position until her death on 31 December 1999. (PROSE: Millennial Rites)


 * Ellie Ravenwood met her future husband, Dave Oswald, after saving him from being hit by a car. Unbeknownst to them, they were watched by the Eleventh Doctor. (TV: The Rings of Akhaten).

January

 * 2 - Actor Victor Carin died from cancer in Edinburgh, Scotland.
 * 3 - TV: Warriors' Gate Part One was first broadcast.
 * 5 - The Hitchhiker's Guide to the Galaxy debuted on BBC Television. A mini-series adaptation of Douglas Adams' radio play and novelisation, the series included a cameo appearance by future Doctor Peter Davison as "The Dish of the Day".
 * 10 - TV: Warriors' Gate Part Two was first broadcast.
 * 15 - PROSE: Doctor Who and the Creature from the Pit was first published. Beginning with this release and continuing through 1991, Target Books commissioned the original teleplay authors to adapt their own scripts whenever possible.
 * 17 - TV: Warriors' Gate Part Three was first broadcast.
 * 24 - TV: Warriors' Gate Part Four was first broadcast. Lalla Ward departed the series with the episode. This was also the final appearance of K9 Mark II. Part 4 concluded the "E-Space Trilogy".
 * 28 - Production of TV: Logopolis concluded, bringing an end to the Tom Baker era.
 * 31 - TV: The Keeper of Traken Part One was first broadcast. Sarah Sutton debuted as new companion Nyssa, although she did not officially become a companion until the next story, and Anthony Ainley made his first appearance on the series, though not yet as the Master.

February

 * The pop band The Human League released the instrumental "Tom Baker" (in honour of the actor) on the flipside of their single "Boys and Girls". This piece of music was later reused for the Project Who radio series in 2005.
 * 7 - TV: The Keeper of Traken Part Two was first broadcast.
 * 14 - TV: The Keeper of Traken Part Three was first broadcast.
 * 21 - TV: The Keeper of Traken Part Four was first broadcast. Anthony Ainley became the newest and longest-serving incarnation of the Master.
 * 21 - Doctor Who theme composer Ron Grainer died.
 * 26 - Actor Gerald Cross died.
 * 28 - TV: Logopolis Part One was first broadcast. Janet Fielding debuted as new companion Tegan Jovanka.

March

 * 5 - Actress Miranda Borman was born.
 * 7 - TV: Logopolis Part Two was first broadcast.
 * 14 - TV: Logopolis Part Three was first broadcast. Sarah Sutton returned as Nyssa and officially became a companion.
 * 21 - TV: Logopolis Part Four was first broadcast, concluding Season 18 and ending with Tom Baker's regeneration into Peter Davison. For the last time until 2005, the lead actor of the series was credited on screen as "Doctor Who". Beginning with the next season, the credit became "The Doctor".
 * 28 - Actor Gareth David-Lloyd was born in Newport, Wales.

April

 * John Nathan-Turner wrote a story outline for the proposed K9 and Company spin-off pilot story.
 * 13 - Studio taping began on TV: Four to Doomsday, the first story of the Peter Davison era to be made, though not the first to be broadcast.
 * 17 - PROSE: Doctor Who and the Enemy of the World was first published. Written by series actor Ian Marter, the book was controversial at the time of release for its use of adult language in a line of books officially considered children's literature. This was the last novelisation in the Target Books line to use the "diamond logo".
 * 28 - Actor Ben Loyd-Holmes was born.

May

 * John Nathan-Turner and Anthony Root composed a "format document" for a planned spin-off series to be entitled K9 and Company.
 * 8 - Actress Ayesha Antoine was born.
 * 12 - Elisabeth Sladen was officially invited to reprise the role of Sarah Jane Smith for the planned K9 and Company spin-off.
 * 21 - REF: The Doctor Who Programme Guide, Volumes 1 and 2, were first published in hardcover.
 * 27 - Writer Kit Pedler died.
 * 29 - Actor Ramsay Williams died.
 * 31 - Composer Jamie Robertson was born.

August

 * The Doctor Who Annual 1982 was published.

September

 * 11 - Actor Lachlan Nieboer was born.
 * 25 - Actor Eric Elliot died.

October

 * 15 - PROSE: Doctor Who and an Unearthly Child, an adaptation of the very first Doctor Who serial, was first published. Its publication promoted the upcoming rebroadcast of the serial by BBC Two as part of their "Five Faces of Doctor Who" special series re-broadcasts. The Target Books line switched to the then-current "neon tubing" series logo with this release.
 * Paperback editions of REF: The Doctor Who Programme Guide Volumes 1 and 2 was published. The books were revised from the hardback versions.
 * 24 - Actress Jemima Rooper was born.

November

 * Production of the pilot episode of the planned K9 and Company spin-off series, TV: A Girl's Best Friend, took place this month.
 * 2 - "The Five Faces of Doctor Who" special re-broadcast series commenced with the third television broadcast of the first part of TV: An Unearthly Child, the very first episode of Doctor Who. It aired in the UK on BBC Two.
 * 3 - The second television broadcast of "The Cave of Skulls" (the second episode of TV: An Unearthly Child) took place in the UK on BBC Two
 * 4 - The second television broadcast of "The Forest of Fear" (the third episode of TV: An Unearthly Child) took place in the UK on BBC Two.
 * 5 - The second television broadcast of "The Firemaker" (the fourth and last episode of TV: An Unearthly Child) took place in the UK on BBC Two.

December

 * REF: The Doctor Who Quiz Book by Nigel Robinson was published.
 * 18 - Actor Joshua Dallas was born.
 * 21 - The final new episode of Terry Nation's Blake's 7 aired on the BBC.
 * 28 - TV: A Girl's Best Friend, a pilot episode for the proposed spin-off K9 and Company, was first broadcast. The pilot reintroduced Sarah Jane Smith and introduced K9 Mark III.

Unknown dates

 * Actor Steven Scott died.
 * Marvel Comics published Marvel Premiere issue 60, bringing to a close the first set of American Fourth Doctor comic strip reprints from Doctor Who Weekly. Another series, Doctor Who, followed in 1984.