An A to Z of all the companion's i have ever had along with me in the tardis throughout the passing years

 (info from wiki )

 A: Abby, Ace, Adric, Alsa,Andric, Anna Good Companions) Antimony, Antranak, Arnold (Children of the Evil Eye), Ayfai

B: Amy Barker, Tony Barker, Barnabus, John Benton, Emily Blandish Jon Bowman, Thomas Brewster, Brod, Adelaide Brooke,Catherine Broome Peri Brown

 C: C'rizz, Susan Campbell, Captain (dog), Jake Carstairs, Vienna Carstairs, Chantir, Dodo Chaplet, Emily Chaudhry, Chertzog Ian Chesterton, Compassion, Raine Creevy, Chris Cwej

D: Sharon Davies, Miranda Dawkins, Oliver Day, Deedrix, Canton Delaware, Destrii, Dot, Tamsin Drew

E: Maxwell Edison, Barnaby Edwards, Erimem

 F: Matthew Finnegan, Finney, Charlie Fisher, Wallace Fitch Jeremy Fitzoliver, Roz Forrester, Frobisher, Edward Fyne

 G: Gemma Griffin, Gisella, Angus Goodman, The Graak, Edward Grainger Grayla, Samson Griffin

 H: Jack Harkness, Oliver Harper, Zoe Heriot, Hex, Hill (The Devil-Birds of Corbo), Will Hoffman, Grace Holloway

J: Jack (The Devil-Birds of Corbo), Ben Jackson, Flip Jackson Joe (Fogbound), John and Gillian, Jo Jones, Martha Jones Samantha Jones, Tegan Jovanka, June (The Slitheen Excursion) Nikki Jupiter, Justin

 K: K9 Mark I, K9 Mark II, K9 Mark III, K9 Mark IV, Kamelion Jason Kane, Anji Kapoor, Katarina, Kevin (robot), Sara Kingdom Elizabeth Klein, Koral, Fitz Kreiner, Kroton (Cyberman)

L: Lammers, Leela, Alistair Gordon Lethbridge-Stewart, Ly-Chee

M: Rok Ma, Sugar MacAuley, Trix MacMillan, Kate Maguire Grant Markham, Marmaduke (Constant Companion), Heather McCrimmon Jamie McCrimmon, Jamie McCrimmon (Land of Fiction), Lucie Miller Adam Mitchell, Sally Morgan, Alan Mortimer, George Mortimer Helen Mortimer, Ida Mortimer, Wilfred Mott

 N: Nyssa

O: Olla

P: Vicki Pallister, Emily Parr, Astrid Peth, Abigail Pettigrew Tom Phipps, Charlotte Pollard, Amy Pond, Majenta Pryce

R: Ria, Cassie Rice, Romana, Romana I, Romana II, Wolfgang Ryter

S: Kazran Sardick, Serena, Liz Shaw, Mary Shelley, Shelly, Izzy Sinclair, Mickey Smith, Sarah Jane Smith, Evelyn Smythe River Song, Christina de Souza, Ssard, Jimmy Stalkingwolf, Strong Harry Sullivan, Bernice Summerfield

T: Bev Tarrant, Steven Taylor, Donna Temple-Noble, Stacy Townsend The Tramp, Fey Truscott-Sade, Vislor Turlough, Jackie Tyler Rose Tyler

W: Victoria Waterfield, Fenella Wibbsey, Billy Wilkins, Rory Williams Guinevere Winchester, Emily Winter, Wolsey, Barbara Wright, Polly Wright

Y: Mike Yates

 Z: Robert Zierath, Zog