1966 (production)

January

 * 7 January - "The Abandoned Planet" was recorded at BBC Television Centre Studio 3. (TCH 6)
 * 7 January - Location filming for The Massacre took place. This took place on Wimbledon Common and covered the sequence where Dodo Chaplet entering the TARDIS. (TCH 7)
 * 14 January - "The Destruction of Time" was recorded at BBC Television Centre Studio 3. (TCH 6)
 * 21 January - "War of God" was recorded at Riverside Studios 1. (TCH 7)
 * 24 January - Pre-filming for The Ark began at Ealing Studios. (TCH 7)
 * 26 January - Innes Lloyd sent scripts of the first two episodes of The Gunfighters to director Rex Tucker.
 * 28 January - "The Sea Beggar" was recorded at Riverside Studios 1. (TCH 7)
 * 31 January - Pre-filming for The Ark continued at Ealing Studios. (TCH 7)

February

 * 4 February - "Priest of Death" was recorded at Riverside Studios 1. (TCH 7)
 * 11 February - "Bell of Doom" was recorded at Riverside Studios 1. (TCH 7)
 * 25 February - John Wiles wrote a memo to Gerald Savory about Gerry Davis's new script for The Celestial Toymaker. In it, he claimed that the central battle of wills between the First Doctor and the Celestial Toymaker had been downplayed to the benefit of new elements involving a more childish confrontation between the companions and the Toymaker's creations. Ultimately, Wiles would have liked to have seen the entire production halted, since its commissioning producer and script editor had gone — and with them, the original, more adult intent of the story.
 * 25 February - "The Plague" was recorded at Riverside Studios 1. (INFO: "The Plague")

March

 * 4 March - "The Return" was recorded at Riverside Studios 1. (INFO: "The Return")
 * 11 March - "The Bomb" was recorded at Riverside Studios 1. (INFO: "The Bomb")
 * 15 March - Pat Dunlop leaves working on The War Machines after partly completing a script for the first episode, due to the script work clashing with pre-existing work he had ongoing on another TV show. Ian Stuart Black takes over the writing duties for this story.
 * 18 March - "The Celestial Toyroom" was recorded at Riverside Studios 1. (TCH 7)
 * 25 March - "The Hall of Dolls" was recorded at Riverside Studios 1. (TCH 7)

April

 * April - The Ocean Liner, The Clock and The Evil Eye are all rejected by Gerry Davis.
 * In late April, the Doctor Who production office circulated a memo to writers outlining the proposed character of the Second Doctor, as well as suggestions on handling the first regeneration, which was initially compared to an LSD trip gone bad.

June

 * 17 June - Episode two of The War Machines was recorded at Riverside Studios 1. (TCH 8)
 * 19-23 June - Location filming for The Smugglers took place. (TCH 8)
 * 24 June - Episode three of The War Machines was recorded at Riverside Studios 1. (TCH 8)

July

 * 1 July - Episode four of The War Machines was recorded at Riverside Studios 1. (TCH 8)
 * 8 July - Episode one of The Smugglers was recorded at Riverside Studios 1. (TCH 8)
 * 15 July - Episode two of The Smugglers was recorded at Riverside Studios 1. (TCH 8)
 * 22 July - Episode three of The Smugglers was recorded at Riverside Studios 1. (TCH 8)
 * 29 July - Episode four of The Smugglers was recorded at Riverside Studios 1. (TCH 8)

August

 * 6 August - The BBC announced to the press that William Hartnell was to leave the role of the first Doctor. Patrick Troughton signed a contract to play the second Doctor for 22 episodes.
 * 30-31 August - Pre-filming for The Tenth Planet took place at Ealing Studios.

September

 * 17 September - Episode one of The Tenth Planet was recorded at Riverside Studios 1. (TCH 8)
 * 24 September - Episode two of The Tenth Planet was recorded at Riverside Studios 1. (TCH 8)
 * 26 - 28 September - Model shots for The Power of the Daleks are filmed.

October

 * 1 October - Episode three of The Tenth Planet was recorded at Riverside Studios 1. (TCH 8)
 * 8 October - Episode four of The Tenth Planet was recorded. Doctor Who's very first regeneration sequence was shot, the beginning of a long-lasting tradition that would keep the show running long after the stars left. This was William Hartnell's final regular day of filming, and Patrick Troughton's first. (TCH 8)
 * 22 October - Episode one of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)
 * 29 October - Episode two of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)

November

 * 5 November - Episode three of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)
 * 12 November - Episode four of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)
 * 19 November - Episode five of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)
 * 26 November - Episode six of The Power of the Daleks was recorded at Riverside Studios 1. (TCH 9)

December

 * 3 December - Episode one of The Highlanders was recorded at Riverside Studios 1. (TCH 9)
 * 10 December - Episode two of The Highlanders was recorded at Riverside Studios 1. (TCH 9)
 * 12 December - The BBC Audience Research Dept. filed an Audience Research Report on The Power of the Daleks Episode 3, reporting that satisfaction in the episode ranked at 44% with response to new Doctor Patrick Troughton being particularly mixed.
 * 15 December - Patrick Troughton was interviewed in Radio Times.
 * 17 December - Episode three of The Highlanders was recorded at Riverside Studios 1. (TCH 9)
 * 24 December - Episode four of The Highlanders was recorded at Riverside Studios 1. (TCH 9)