Lakertya is the planet on which the serial Time and the Rani is set.
Logopolis is the planet on which much of the action in the serial Logopolis is set. It is home to a race of mathematicians who are masters of Block Transfer Computation.
M
Manussa is the setting of the Fifth Doctor serial Snakedance .
Mechanus is the jungle homeworld of the Mechanoids in The Chase .
Metebelis Three is where the Third Doctor takes a perfect blue crystal from in The Green Death , and where he returns to in the serial Planet of the Spiders.
Minyos is the original homeworld of the Minyans, and Minyos II is where they settle at the end of the serial Underworld .
Pluto is the setting of the Fourth Doctor serial The Sun Makers , in which it is endowed with six suns and a breathable atmosphere.
Q
R
Ravolox is the titular planet of The Mysterious Planet. It is actually Earth, displaced by the Time Lords through time and space and renamed. It features a black light pinnacle of tremendous power.
Refusis is the destination for the refugees of humanity in The Ark , as they flee the devastation of Earth by the Sun in AD 10,000,000.
The planet Ribos is the setting for the start of the quest for the Key to Time, The Ribos Operation .
S
Sarn is the Planet of Fire in the Fifth Doctor serial of that name.
Segonax is where the Psychic Circus is perfoming in The Greatest Show in the Galaxy
Spiridon is an inhospitable planet, home to the Spiridons, a race of beings with the natural ability to become invisible. The Daleks kept a secret army there in Planet of the Daleks.
Svartos is the location of Iceworld in the serial Dragonfire .
T
Tara is the setting of the Fourth Doctor serial The Androids of Tara .
Tigella is the neighbouring planet to Zolfa Thura in Meglos .
Daisy K's misery-free colony in The Happiness Patrol is on the planet Terra Alpha.
Thoros Alpha and Thoros Beta are planets featured in Mindwarp. Thoros Beta is home to the Mentors, an amphibious race. The Doctor first encounters a Mentor - Sil - in Vengeance on Varos and mention of Thoros Beta is made in that serial.
Traken was the homeworld to a race of pacifists. It was first seen in The Keeper of Traken and destroyed by a wave of entropy in Logopolis. The Doctor's companion, Nyssa, was a native of Traken.
U
Uxaerius is the location of the Doomsday Weapon in the Third Doctor serial Colony in Space .
V
Varos is the setting of the Sixth Doctor serial Vengeance on Varos .
Vortis is the setting of the First Doctor serial The Web Planet; the Menoptra and Zarbi were indigenous species.
Vulcan is home to a human colony in the Second Doctor serial The Power of the Daleks . It has no connection to Vulcan (Star Trek).
X
Xeros is the location of The Space Museum , the First Doctor serial of that name.
Xeriphas is a planet visited by the Fifth Doctor in Time Flight .
Z
Zanak is the The Pirate Planet, a planet which can materialise around other planets and steal their mineral wealth.
Zeos is one of the planets at war in The Armageddon Factor .
Zeta Minor is the farthest planet out in the known universe, and contains samples of antimatter. It was first seen in Planet of Evil .
Zolfa Thura is an apparently barren world in Meglos .
Notes
E-Space, or Exo-space, is another universe connected to our own by Charged Vacuum Emboitments, through which entropy is vented from our universe to stave off the heat death of the universe. It contains its own planets, including Adric's homeworld, Alzarius.
N-Space, or Normal-space, is our universe, where heat death should have already occurred, but for the Logopolitans' creation of the CVEs to shunt the excess entropy into other universes, including E-space. Unless otherwise noted, all planets listed are in N-Space.
Terminus is not a planet, but a planet-sized spacecraft that caused the Big Bang and lies at the centre of the universe . Its engines are capable of causing another explosion that will end the universe, and the radiation leaking from them is the cure for Lazar's Disease.