31 July is the 212nd day of the year (213th in leap years). There are 153 days remaining until the end of the year.
- Hogwarts School of Witchcraft and Wizardry expects to receive an owl confirming the receipt of the Hogwarts acceptance letter by non-Muggle-born students by this date.
- 1980: Harry James Potter is born to James and Lily Potter
- 1991: Rubeus Hagrid arrives at the Hut-on-the-Rock shortly after midnight and delivers Harry Potter his Hogwarts acceptance letter. Hagrid takes Harry on his first visit to Diagon Alley. Quirinus Quirrell breaks into Gringotts Wizarding Bank, but fails to steal the Philosopher's Stone as the vault containing it had already been emptied earlier in the day.
- 1992: The Dursleys have dinner with Mr. and Mrs. Mason. Dobby visits Harry, and warns him not to return to Hogwarts. Dobby casts a Hover Charm on a pudding, but it is Harry who receives an official warning from the Ministry of Magic for Underage magic, presuming Harry is the only wizard in the area.
- 1993: Marge Dursley arrives at 4 Privet Drive, for a week with her brother, sister-in-law, and nephew.
- 1994: Harry receives cakes and sweets from Ron Weasley, Hermione Granger, Sirius Black, and Rubeus Hagrid.
- 1995: Harry receives boxes of Honeydukes sweets from Ron and Hermione, but throws them away because he is upset with them. Dudley Dursley and his gang beat up ten-year-old Mark Evans.
- 1996: Harry celebrates his 16th birthday at the Burrow, the celebrations are marred by grisly tidings from Remus Lupin of more Dementor attacks and Igor Karkaroff's body is found in a shack up north.
- 1997: A birthday party for Harry is held at the Burrow. Ginny Weasley gives Harry a birthday kiss, angering her brother. Minister for Magic Rufus Scrimgeour crashes the party and gives Harry, Ron, and Hermione objects from Albus Dumbledore's will.
- 1998: The Daily Prophet prints an article entitled: MUGGLES NOT AS STUPID AS WE THINK, SAYS MINISTRY REPORT.
- 2014: Dumbledore's Army: The Dark Side of the Demob is released at Flourish and Blotts.
Behind the scenes
- 1947: Richard Griffiths, the actor who portrayed Vernon Dursley is born.
- 1965: J. K. Rowling, the author of the Harry Potter series is born.
- 2011: J. K. Rowling, the author of the Harry Potter series, opens the Pottermore Registration for a few lucky people who are able to get in Pottermore earlier.