All official subclasses now that Xanathar's content is confirmed (includes PHB, SCAG, and XGE).
Barbarian: Ancestral Guardian, Battlerager, Beserker, Storm Herald, Totem Warrior, Zealot
Bard: Glamour, Lore, Swords, Valor, Whispers
Cleric: Arcana, Death, Forge, Grave, Knowledge, Life, Light, Nature, Tempest, Trickery, War
Druid: Dreams, Land, Moon, Shepherd
Fighter: Arcane Archer, Battle Master, Cavalier, Champion, Eldritch Knight, Samurai
Monk: Drunken Master, Four Elements, Kensei, Long Death, Open Hand, Shadow, Sun Soul
Paladin: Ancients, Conquest, Crown, Devotion, Oathbreaker, Redemption, Vengence
Ranger: Beast Master, Gloom Stalker, Horizon Walker, Hunter, Monster Slayer
Rogue: Arcane Trickster, Assassin, Inquisitive, Mastermind, Scout, Swashbuckler, Thief
Sorcerer: Divine Soul, Draconic Bloodline, Shadow Magic, Storm Sorcery, Wild Magic
Warlock: The Archfey, The Celestial, The Fiend, The Great Old One, The Hexblade, The Undying
Wizard: Abjuration, Bladesinger, Conjuration, Divination, Enchantment, Evocation, Illusion, Necromancy, Trasmutation, War Magic