Pets

Wizard families, like Muggle families, often like to have pets. However, pets in the wizarding world usually show some "interesting powers" and live longer than Muggle animals (GF4). Two magical pet stores are in Diagon Alley: Eeylops Owl Emporium, where Hagrid bought Hedwig for Harry's eleventh birthday, and the Magical Menagerie, where Hermione bought Crookshanks (SS5, PA4).

Hogwarts students are allowed to have an owl, a cat, or a toad, but this rule doesn't seem to be strictly enforced. Percy and Ron Weasley had Scabbers, the rat, and Lee Jordan had a giant tarantula. The owls live in the Owlery, but the other pets usually remain in the students' dormitories and common rooms. However, Ron often carries Scabbers around, and Neville has taken his toad Trevor with him to classes, as Professor Flitwick made Trevor zoom around the room in Charms, and Snape fed Trevor Shrinking Potion (SS5, 6, 7, 10, 16; PA5, 7; GF20).

Acromantula - Hagrid (and only Hagrid) had a pet Acromantula, which is a highly dangerous giant spider that likes to eat humans (FB, CS15, GF31, OP16)

Aragog -the name of Hagrid's Acromantula; Aragog was released into the Forbidden Forest when Hagrid was expelled from Hogwarts; Hagrid found a wife, Mosag, for him (CS15)

Basilisk - the monster in the Chamber of Secrets; it would only obey Salazar Slytherin or his heir (CS16, 17)

Binky - Lavender Brown's pet rabbit, which was killed by a fox in the third year (PA8)

Blast-Ended Skrewt - as Draco Malfoy said, "Who wouldn't want pets that can burn, sting, and bite all at once?" (GF13)

Buckbeak - originally Hagrid's Hippogriff; Harry and Hermione saved Buckbeak from execution; Sirius Black escaped from Hogwarts on Buckbeak, then took care of him at Twelve Grimmauld Place (PA6, 11, 14, 15, 16, 21; OP6, 24, 37)

Cat - students at Hogwarts are allowed to have an owl, a cat, or a toad; there are lots of cats on Platform Nine and Three Quarters (SS5, 6)

Crookshanks - Hermione purchased Crookshanks, a half-Kneazle, at the Magical Menagerie in Diagon Alley (PA4, 5, 8, 11, 15, 17, 19; GF5; OP5; JKR website)

Dragon - only Hagrid would want a dragon for a pet, and for a brief time he had a pet dragon named Norbert (SS5, 14)

Errol - the owl belonging to the Weasley family (CS3, 6; PA1; GF3)

Fang - Hagrid's boarhound, a very large and slobbery dog; despite his name, he is rather cowardly, but he fiercely defended Hagrid when the Aurors came to arrest him (SS8, 15; CS15; OP31)

Fawkes -Dumbledore's pet phoenix (FB; CS12, 17; GF30, 36; OP22, 27, 36, 37)

Fluffy - Hagrid's three-headed dog, which guarded the Sorcerer's Stone; he is now running wild in the Forbidden Forest (SS9, 11, 16; JKR interview)

Frogs - Petunia said Lily came home from Hogwarts with pockets full of frog spawn; in Ron's room there was a fish tank full on frog spawn; two years later the fish tank held an extremely large frog (SS4, CS3, GF5)

Grindylow - a merperson's home had a pet grindylow staked outside the door (FB, GF26)

Hedwig - Harry's first real birthday present was Hedwig, the snowy owl that Hagrid purchased for him; Hedwig is extremely intelligent, can understand human speech, anticipates Harry's needs, and can deliver a letter to anyone (SS5, 6, 8; CS3, 12; PA1; GF14; OP3, 14, 17, 18)

Hermes - the owl belonging to Percy Weasley (CS3, OP14)

Hippogriff - Hagrid had a pet Hippogriff named Buckbeak; Sirius took over Buckbeak's care (FB; PA6, 11, 14, 15, 16, 21; OP6, 24, 37)

Kneazles - Newt Scamander and his wife, Porpentina, have three pet Kneazles; Arabella Figg breeds part-Kneazles (FB, OP15, JKR website)

Mr. Paws - one of Arabella Figg's cat-Kneazles (SS2, JKR website)

Mr. Tibbles, Tibbles - one of Arabella Figg's cat-Kneazles; it helped her keep watch over the Dursleys' house (SS2, OP2, JKR website)

Mrs. Norris - the pet cat of Argus Filch, with whom he has an almost telepathic connection (SS8, 9; CS8, 9; OP14)

Nagini - the snake belonging to Lord Voldemort (GF1, 29, 33)

Norbert - Hagrid briefly had Norbert, a Norwegian Ridgeback dragon (SS14)

Owl - students at Hogwarts are allowed to have an owl, a cat, or a toad (SS5)

Parrot - Dudley Dursley had a pet parrot, but he swapped it for an air rifle (SS3)

Phoenix - Fawkes is Professor Dumbledore's pet phoenix and lives in his office; a phoenix is a magical bird about the size of a swan; very few wizards have ever domesticated it (FB; CS12, 17; GF30, 36; OP22, 27, 36, 37)

Pigwidgeon or "Pig" - Sirius Black gave Pigwidgeon, a tiny owl, to Ron Weasley; Ginny gave Pig his name (PA22; GF3, 5, 23)

Puffskein - a small, pleasant creature often kept as pets by wizard children; Ron Weasley used to own one until Fred used it for Bludger practice (FB, OP5)

Rat - first Percy, then Ron Wealsey, had a pet rat, Scabbers (SS6; PA4, 5, 8, 11, 12, 16, 17, 18, 19)

Ripper - the pet bulldog belonging to Marge Dursley (PA2)

Runespoor - a magical, three-headed snake that grows 6 to 7 feet long, it is a favorite pet of dark wizards (FB)

Scabbers - the Weasley family's pet rat, who was really the animagus of Peter Pettigrew (SS6; PA4, 5, 8, 11, 12, 16, 17, 18, 19)

Snake - Lord Voldemort had pet snake, Nagini (GF1, 29, 33)

Snowy - one of Arabella Figg's cat-Kneazles (SS2, JKR website)

Tarantula, giant - Lee Jordan had one on Platform Nine and Three Quarters at the start of Harry's first year (PS6)

Toads - students at Hogwarts are allowed to have an owl, a cat, or a toad, but toads are out of fashion (SS5)

Tortoise - Dudley chucked his pet tortoise through the greenhouse roof when he was angry about Harry moving into his second bedroom (SS3)

Trevor - Neville Longbottom's pet toad, which was given to him by his Great-Uncle Algie; Trevor tends to keep disappearing; Neville often carries Trevor around with him as Professor Flitwick made Trevor zoom around the room in Charms class, and Snape fed Trevor Shrinking Potion (SS6, 7, 10, 16; PA5, 7; GF20)

Tufty - one of Arabella Figg's cat-Kneazles (SS2, JKR website)