The story follows the life of David Copperfield from childhood to maturity. David was born in Blunderstone, Suffolk, England, six months after the death of his father. David spends his early years residing in a small house called the Rookery. His loving and childish mother and their kindly housekeeper, Clara Peggotty, raise him here, where they call him Davy. When he is seven years old his mother marries Edward Murdstone without having told him they plan to marry. To get him out of the way, David is sent to visit with Peggotty's family in Yarmouth. Her brother, fisherman Mr Peggotty, lives in a beached barge, with his adopted niece and nephew Emily and Ham, and an elderly widow, Mrs Gummidge. "Little Em'ly" is somewhat spoiled by her fond foster father, and David is in love with her. They call him Master Copperfield.
On his return, David discovers his mother has married and is immediately given good reason to dislike his stepfather, Murdstone, who believes exclusively in stern, harsh methods of parenting, calling it "firmness". David has similar feelings for Murdstone's sister Jane, who moves into the house soon afterwards. Between them they tyrannise his poor mother, making David's and her lives miserable, and when, in consequence, David falls behind in his studies, Murdstone attempts to thrash him – partly to give further pain his mother. David bites him and soon afterwards is sent away to Salem House, a boarding school, under a ruthless headmaster named Mr Creakle. There he is befriended by an older boy, James Steerforth, and Tommy Traddles. He develops an impassioned admiration for Steerforth, perceiving him as someone noble, who could do great things if he would, and one who pays attention to him.
David goes home for the holidays to learn that his mother has given birth to a baby boy. Shortly after David returns to Salem House, his mother and her baby die, and David returns home immediately. Peggotty marries the local carrier, Mr Barkis. Murdstone sends David to work for a wine merchant in London – a business of which Murdstone is a joint owner. After some months, David's friendly but spendthrift landlord, Wilkins Micawber, is arrested for debt and sent to the King's Bench Prison. On one of David's visits, Micawber advises David to head to Dover to find his only known remaining relative, his eccentric and kind-hearted great-aunt Betsey Trotwood. After Micawber is released and has moved to Plymouth, no one in London cares about David, so he decides to run away to his aunt. She had come to Blunderstone at his birth, only to depart in ire upon learning that he was not a girl. However, she takes it upon herself to raise David, despite Murdstone's attempt to regain custody of him. She encourages him to 'be as like his sister, Betsey Trotwood' as he can be – that is, to meet the expectations she had for the girl who was never born. David's great-aunt renames him "Trotwood Copperfield" and addresses him as "Trot", one of several names others call David in the novel.
David's aunt sends him to a better school than the last he attended. It is run by kind Dr. Strong, whose methods inculcate honour and self-reliance in his pupils. During term, David lodges with the lawyer Mr Wickfield and his daughter Agnes, who becomes David's friend and confidante. Wickfield's clerk, Uriah Heep, also lives at the house.
By devious means, Uriah Heep gradually gains a complete ascendancy over the aging and alcoholic Wickfield, to Agnes's great sorrow. Heep, as he maliciously confides to David, aspires to marry Agnes. Ultimately with the aid of Micawber, who has been employed by Heep as a secretary, his fraudulent behaviour is revealed. (At the end of the book, David encounters him in prison, convicted of attempting to defraud the Bank of England.)
After completing school, David apprentices to be a proctor. During this time, due to Heep's fraudulent activities, his aunt's fortune has diminished. David toils to make a living. He works mornings and evenings for his former teacher Dr Strong as a secretary, and also starts to learn shorthand, with the help of his old school-friend Traddles, upon completion reporting parliamentary debate for a newspaper. With considerable moral support from Agnes and his own great diligence and hard work, David ultimately finds fame and fortune as an author, writing fiction.
David's romantic but self-serving school friend, Steerforth, also re-acquainted with David, goes on to seduce and dishonour Emily, offering to marry her off to his manservant Littimer before deserting her in Europe. Her uncle Mr Peggotty manages to find her with the help of Martha, who had grown up in their part of England and then settled in London. Ham, who had been engaged to marry Emily before the tragedy, dies in a fierce storm off the coast while rescuing shipwreck victims. Steerforth was aboard the ship and also dies. Mr Peggotty takes Emily to a new life in Australia, accompanied by Mrs Gummidge and the Micawbers, where all eventually find security and happiness.
David, meanwhile, has fallen completely in love with Dora Spenlow, and then marries her. Their marriage proves troublesome for David in the sense of everyday practical affairs, but he never stops loving her. Dora dies early in their marriage after a miscarriage. After Dora's death, Agnes encourages David to return to normal life and his profession of writing. While living in Switzerland to dispel his grief over so many losses, David realises that he loves Agnes. Upon returning to Britain, after a failed attempt to conceal his feelings, David finds that Agnes loves him too. They quickly marry, and in this marriage he finds true happiness. David and Agnes then have at least five children, including a daughter named after his great-aunt, Betsey Trotwood.
