Rowling was born to Peter James Rowling, a Rolls-Royce aircraft Engineer, and Anne Rowling (née Volant), a science technician, on 31 July 1965 in Yate, Gloucestershire, England, 10 miles (16 km) northeast of Bristol. Her parents first met on a train departing from King's Cross Station bound for Arbroath in 1964. They married on 14 March 1965. One of her maternal great-grandfathers, Dugald Campbell, was Scottish, born in Lamlash on the Isle of Arran. Her mother's paternal grandfather, Louis Volant, was French, and was awarded the Croix de Guerre for exceptional bravery in defending the village of Courcelles-le-Comte during the First World War. Rowling originally believed he had won the Légion d'honneur during the war, as she said when she received it herself in 2009. She later discovered the truth when featured in an episode of the UK genealogy series Who Do You Think You Are?, in which she found out it was a different Louis Volant who won the Legion of Honour. When she heard his story of bravery and discovered the croix de guerre was for "ordinary" Soldiers like her grandfather, who had been a waiter, she stated the croix de guerre was "better" to her than the Legion of Honour.

In 1982, Rowling took the entrance exams for Oxford University but was not accepted and earned a BA in French and Classics at the University of Exeter. Martin Sorrell, a French professor at Exeter, remembers "a quietly competent student, with a denim jacket and dark hair, who, in academic terms, gave the appearance of doing what was necessary". Rowling recalls doing little work, preferring to read Dickens and Tolkien. After a year of study in Paris, Rowling graduated from Exeter in 1986. In 1988, Rowling wrote a short essay about her time studying Classics titled "What was the Name of that Nymph Again? or Greek and Roman Studies Recalled"; it was published by the University of Exeter's journal Pegasus.

Rowling has contributed money and support for research and treatment of multiple sclerosis, from which her mother suffered before her death in 1990. In 2006, Rowling contributed a substantial sum toward the creation of a new Centre for Regenerative Medicine at Edinburgh University, later named the Anne Rowling Regenerative Neurology Clinic. In 2010 she donated a further £10 million to the centre. For reasons unknown, Scotland, Rowling's country of adoption, has the highest rate of multiple sclerosis in the world. In 2003, Rowling took part in a campaign to establish a national standard of care for MS sufferers. In April 2009, she announced that she was withdrawing her support for Multiple Sclerosis Society Scotland, citing her inability to resolve an ongoing feud between the organisation's northern and southern branches that had sapped morale and led to several resignations.

An advertisement in The Guardian led Rowling to move to Porto, Portugal, to teach English as a foreign language. She taught at night and began writing in the day while listening to Tchaikovsky's Violin Concerto. After 18 months in Porto, she met Portuguese television Journalist Jorge Arantes in a bar and found they shared an interest in Jane Austen. They married on 16 October 1992 and their child, Jessica Isabel Rowling Arantes (named after Jessica Mitford), was born on 27 July 1993 in Portugal. Rowling had previously suffered a miscarriage. The couple separated on 17 November 1993. Biographers have suggested that Rowling suffered domestic abuse during her marriage, although the extent is unknown. In December 1993, Rowling and her then-infant daughter moved to Edinburgh, Scotland, to be near Rowling's sister with three chapters of what would become Harry Potter in her suitcase.

Rowling was left in despair after her estranged husband arrived in Scotland, seeking both her and her daughter. She obtained an Order of Restraint, and Arantes returned to Portugal, with Rowling filing for divorce in August 1994. She began a Teacher training course in August 1995 at the Moray House School of Education, at Edinburgh University, after completing her first novel while living on state benefits. She wrote in many cafés, especially Nicolson's Café (owned by her brother-in-law), and the Elephant House, wherever she could get Jessica to fall asleep. In a 2001 BBC interview, Rowling denied the rumour that she wrote in local cafés to escape from her unheated flat, pointing out that it had heating. One of the reasons she wrote in cafés was that taking her baby out for a walk was the best way to make her fall asleep.

In 1995, Rowling finished her manuscript for Harry Potter and the Philosopher's Stone on an old manual typewriter. Upon the enthusiastic response of Bryony Evens, a reader who had been asked to review the book's first three chapters, the Fulham-based Christopher Little Literary Agency agreed to represent Rowling in her quest for a publisher. The book was submitted to twelve publishing houses, all of which rejected the manuscript. A year later she was finally given the green light (and a £1,500 advance) by Editor Barry Cunningham from Bloomsbury, a publishing house in London. The decision to publish Rowling's book owes much to Alice Newton, the eight-year-old daughter of Bloomsbury's chairman, who was given the first chapter to review by her father and immediately demanded the next. Although Bloomsbury agreed to publish the book, Cunningham says that he advised Rowling to get a day job, since she had little chance of making money in children's books. Soon after, in 1997, Rowling received an £8,000 grant from the Scottish Arts Council to enable her to continue writing.

In June 1997, Bloomsbury published Philosopher's Stone with an initial print run of 1,000 copies, 500 of which were distributed to libraries. Today, such copies are valued between £16,000 and £25,000. Five months later, the book won its first award, a Nestlé Smarties Book Prize. In February, the novel won the British Book Award for Children's Book of the Year, and later, the Children's Book Award. In early 1998, an auction was held in the United States for the rights to publish the novel, and was won by Scholastic Inc., for US$105,000. Rowling said that she "nearly died" when she heard the news. In October 1998, Scholastic published Philosopher's Stone in the US under the title of Harry Potter and the Sorcerer's Stone, a change Rowling says she now regrets and would have fought if she had been in a better position at the time. Rowling moved from her flat with the money from the Scholastic sale, into 19 Hazelbank Terrace in Edinburgh.

Its sequel, Harry Potter and the Chamber of Secrets, was published in July 1998 and again Rowling won the Smarties Prize. In December 1999, the third novel, Harry Potter and the Prisoner of Azkaban, won the Smarties Prize, making Rowling the first person to win the award three times running. She later withdrew the fourth Harry Potter novel from contention to allow other books a fair chance. In January 2000, Prisoner of Azkaban won the inaugural Whitbread Children's Book of the Year award, though it lost the Book of the Year prize to Seamus Heaney's translation of Beowulf.

Rowling, once a single parent, is now President of the charity Gingerbread (originally One Parent Families), having become their first Ambassador in 2000. Rowling collaborated with Sarah Brown to write a book of children's stories to aid One Parent Families.

In 2001, the UK anti-poverty fundraiser Comic Relief asked three best-selling British authors – cookery Writer and TV presenter Delia Smith, Bridget Jones creator Helen Fielding, and Rowling – to submit booklets related to their most famous works for publication. Rowling's two booklets, Fantastic Beasts and Where to Find Them and Quidditch Through the Ages, are ostensibly facsimiles of books found in the Hogwarts library. Since going on sale in March 2001, the books have raised £15.7 million for the fund. The £10.8 million they have raised outside the UK have been channelled into a newly created International Fund for Children and Young People in Crisis. In 2002 Rowling contributed a foreword to Magic, an anthology of fiction published by Bloomsbury Publishing, helping to raise money for the National Council for One Parent Families.

In 2004, Forbes named Rowling as the first person to become a US-dollar Billionaire by writing books, the second-richest female entertainer and the 1,062nd richest person in the world. Rowling disputed the calculations and said she had plenty of money, but was not a Billionaire. The 2016 Sunday Times Rich List estimated Rowling's fortune at £600 million, ranking her as the joint 197th richest person in the UK. In 2012, Forbes removed Rowling from their rich list, claiming that her US$160 million in charitable donations and the high tax rate in the UK meant she was no longer a Billionaire. In February 2013 she was assessed as the 13th most powerful woman in the United Kingdom by Woman's Hour on BBC Radio 4.

Rowling is a friend of Sarah Brown, wife of former prime minister Gordon Brown, whom she met when they collaborated on a charitable project. When Sarah Brown's son Fraser was born in 2003, Rowling was one of the first to visit her in hospital. Rowling's youngest child, daughter Mackenzie Jean Rowling Murray, to whom she dedicated Harry Potter and the Half-Blood Prince, was born on 23 January 2005.

In a 2006 interview with Tatler magazine, Rowling noted that, "like Graham Greene, my faith is sometimes about if my faith will return. It's important to me." She has said that she has struggled with doubt, that she believes in an afterlife, and that her faith plays a part in her books. In a 2012 radio interview, she said that she was a member of the Scottish Episcopal Church, a province of the Anglican Communion.

In 2007, Rowling described having been brought up in the Church of England. She said she was the only one in her family who regularly went to church. As a student she became annoyed at the "smugness of religious people" and worshipped less often. Later, she started to attend again at a church in Edinburgh.

Rowling has received honorary degrees from St Andrews University, the University of Edinburgh, Edinburgh Napier University, the University of Exeter which she attended, the University of Aberdeen and Harvard University, for whom she spoke at the 2008 commencement ceremony. In 2009 Rowling was made a Chevalier de la Légion d'honneur by French President Nicolas Sarkozy. In 2011 Rowling became an honorary Fellow of the Royal College of Physicians of Edinburgh.

In April 2010, Rowling published an article in The Times, in which she criticised Cameron's plan to encourage married couples to stay together by offering them a £150 annual tax credit: "Nobody who has ever experienced the reality of poverty could say 'it's not the money, it's the message'. When your flat has been broken into, and you cannot afford a locksmith, it is the money. When you are two pence short of a tin of baked beans, and your child is hungry, it is the money. When you find yourself contemplating shoplifting to get nappies, it is the money."

In September 2011, Rowling was named a "core participant" in the Leveson Inquiry into the culture, practices and ethics of the British press, as one of dozens of celebrities who may have been the victim of phone hacking. On 24 November 2011, Rowling gave evidence before the inquiry; although she was not suspected to have been the victim of phone hacking, her testimony included accounts of Photographers camping on her doorstep, her fiancé being duped into giving his home address to a Journalist masquerading as a tax official, her chasing a Journalist a week after giving birth, a Journalist leaving a note inside her then-five-year-old daughter's schoolbag, and an attempt by The Sun to "blackmail" her into a photo opportunity in exchange for the return of a stolen manuscript. Rowling claimed she had to leave her former home in Merchiston because of press intrusion. In November 2012, Rowling wrote an article for The Guardian in reaction to David Cameron's decision not to implement the full recommendations of the Leveson inquiry, saying she felt "duped and angry".

In July 2012, Rowling was featured at the 2012 Summer Olympics opening ceremony in London where she read a few lines from J. M. Barrie's Peter Pan as part of a tribute to Great Ormond Street Hospital for Children. An inflatable representation of Lord Voldemort and other children's literary characters accompanied her reading.

Soon after the revelation, Brooks pondered whether Jude Callegari could have been Rowling as part of wider speculation that the entire affair had been a publicity stunt. Some also noted that many of the Writers who had initially praised the book, such as Alex Gray or Val McDermid, were within Rowling's circle of acquaintances; both vociferously denied any foreknowledge of Rowling's authorship. Judith "Jude" Callegari was the best friend of the wife of Chris Gossage, a partner within Russells Solicitors, Rowling's legal representatives. Rowling released a statement saying she was disappointed and angry; Russells apologised for the leak, confirming it was not part of a marketing stunt and that "the disclosure was made in confidence to someone he [Gossage] trusted implicitly". Russells made a donation to the Soldiers' Charity on Rowling's behalf and reimbursed her for her legal fees. On 26 November 2013 the Solicitors Regulation Authority (SRA) issued Gossage a written rebuke and £1,000 fine for breaching privacy rules.

In 2014, Rowling reaffirmed her support for "Hacked Off" and its campaign towards press self-regulation by co-signing with other British celebrities a declaration to "[safeguard] the press from political interference while also giving vital protection to the vulnerable."

In 2015, following the referendum on same-sex marriage in Ireland, Rowling joked that if Ireland legalised same-sex marriage, Dumbledore and Gandalf could get married there. The Westboro Baptist Church, in response, stated that if the two got married, they would picket. Rowling responded by saying "Alas, the sheer awesomeness of such a union in such a place would blow your tiny bigoted minds out of your thick sloping skulls."

In June 2016, Rowling campaigned against the Referendum to leave the European Union, stating on her website that, "I'm the mongrel product of this European continent and I'm an internationalist. I was raised by a Francophile mother whose family was proud of their part-French heritage ... My values are not contained or proscribed by borders. The absence of a visa when I cross the channel has symbolic value to me. I might not be in my house, but I'm still in my hometown."

She was appointed Member of the Order of the Companions of Honour (CH) in the 2017 Birthday Honours for services to literature and philanthropy.