Del Boy is a happy-go-lucky cheeky character. While not always successful, his general optimism and confidence often persuade people to believe in him. From the sixth series on, he adopts some of the mannerisms of a stereotypical yuppie of the late 1980s, pretending to be much more wealthy than he really is, as he tries to associate with the upper classes despite being obviously working class.
Del Boy is a habitual liar, particularly to women, customers, policemen and even his family and doctors. He sometimes lies when it is against his best interests, such as when he claims to be a health freak while suffering from stomach pains, leading to his spending several days under observation in hospital rather than receiving an immediate diagnosis.
It is revealed in Sickness and Wealth that he is frightened of doctors, which causes him to resist Albert and Rodney's advice for him to see a doctor, until a medium tricks him into believing his departed mother wants him to visit the doctor about his stomach. In Fatal Extraction, it is revealed that Del is also frightened of dentists, avoiding visiting them whenever possible (his previous dentist died on the night of the Queen's Silver Jubilee in 1977) and only reluctantly visiting due to bad toothache.
Del presents himself as being able to speak some French, though few of his phrases make any sense in the context he uses them in (e.g. saying "au revoir" to mean "hello" and "bonjour" as goodbye). He also thinks he has knowledge in subjects like geography (believing Stockholm to be in Norway), history, art and other academic subjects (his lack of knowledge in history is shown well in "To Hull and Back" in which he calls Albert "the finest little sailor this country has produced since Nelson lost the Armada".) He believes the term "yuppie" to be a compliment, and unintentionally causes considerable offence when he calls a person a yuppie to their face.
Del Boy is not always outspoken when expressing his love for his family and others, but this side of his nature is shown in numerous episodes, such as "Diamonds Are for Heather", "Strained Relations", "Dates", "The Yellow Peril" and "Little Problems". His care for his grandfather ("Grandad" – Lennard Pearce) is shown in "The Second Time Around", when Grandad confesses to having Trigger phone to tell Del that his fiancée, Pauline Harris, has killed her husband Bobby Finch by poisoning him. Another example of this care is shown in "May the Force be With You". Faced with the possibility of he and Rodney going to prison for handling a stolen microwave, corrupt policeman Roy Slater makes a veiled threat suggesting that a now-alone and vulnerable Grandad could fall victim to an attack by some hired thugs. Del, having hitherto refused to name the thief, makes a deal with Slater to guarantee their release, with immunity from prosecution for doing so. Once he is given immunity from prosecution, he names himself as the thief.
Del is later diagnosed with Irritable bowel syndrome caused by his diet of fast foods, cigars and alcohol.
Although engaged many times, he never marries. He has had many girlfriends, a fact that is the subject of numerous harsh comments by Rodney. He finally meets his partner Raquel Turner (whom he calls his "significant other") in the 1988 special "Dates".
Del's mother Joan dies on 12 March 1964, apparently after a long string of illnesses. His lazy father Reginald leaves three months later (on Del's 16th birthday), taking most of their money and even Del's birthday cake, leaving the teenage Del as the family's sole breadwinner, looking after his grandfather and Rodney, his half-brother who was born fifteen years after him in 1960. He lives with Rodney, Cassandra, Raquel and their son Damien at door 368 on the twelfth floor of the fictional Nelson Mandela House in the Dockside Estate, Peckham, London. Before that, he lives in an old detached house in 39 Orchard Street with his mother, father and grandfather. His grandfather was an "out of work lamp-lighter, waiting for gas to make a comeback." In the episode Sleepless in Peckham Del gives the implication that his father was also a physically abusive man who used to beat women and children, including Joan and Del. Del's father was a mate of Freddie Robdal, who became better known as Freddie the Frog. It was Del's father who also brought Freddie to his home one night which led to an affair between him and Joan, and soon after, the birth of Rodney. When he was a youngster, Del always was told to call Freddie "Uncle Fred". Then, years later, when Uncle Albert got drunk one night at an old folks party, he told Del all about the affair. Some time afterwards, Uncle Albert told Del that Del's aunt Rene took all the photos of Del's mum because every one had a picture of Freddie in it, and she knew that when Rodney grew older the similarities would start to show, so she burnt all the photos of Joan after her funeral.
Del Boy has many girlfriends during the series. His friends include Trigger, Denzil, Boycie, Marlene and Mike. His nemesis is DCI Roy Slater. Del is brave and, although not intellectual, he is quick-witted and frequently gets Rodney into trouble. In "Wanted", when a mentally unstable woman accuses Rodney of attacking her, Del makes a joke of it and says that the police have named Rodney "The Peckham Pouncer". Del is afraid of doctors and dentists. His favourite song is "Old Shep", and his favourite band is The Who. In "Rodney Come Home", Del hints that he supports Millwall F.C., but in "The Long Legs of the Law" he implies that he supports Chelsea. In "A Slow Bus to Chingford" Rodney tells his date Janice that Del "used to be cultural advisor to the Chelsea Shed", a reference to the Shed End at Stamford Bridge where the most fanatical Chelsea fans would stand. He believes himself fluent in French but confuses bonjour and au revoir. He cannot swim – the certificate in his possession is not his – nor fly a hang glider. He is not very intelligent, but can be very considerate, such as when he tried to help Rodney get over his wife Cassandra's miscarriage of their first baby. He never hesitates to remind people about how he brought Rodney up practically on his own after their mother died and father left, often using this fact to win arguments with Rodney. He is also shown to be particularly sly, once described by corrupt policeman and former school "friend" Roy Slater as "A man who could talk himself out of a room with no doors". In "May the Force Be With You", he was arrested by Slater for handling a stolen microwave, but gained his release by agreeing to name the thief provided he and his family were granted immunity from prosecution. Once Del's immunity was guaranteed, he confessed that he was the thief, gleefully showing a horrified Slater his immunity papers.
Del and Rodney often tease Uncle Albert about his appearance and resemblance to Captain Birdseye, although they show fonder feelings for him when he dies in "If They Could See Us Now". Rodney apologises for the way he treats Albert in "Sickness and Wealth".
In Rock & Chips, Del Boy is shown to have a particularly close relationship with his mother Joan, whom he loves dearly. (He is Joan's favourite, to the point that she refuses to run away with Freddie Robdal until she is certain of Del's financial security.) His relationship with Grandad is the same in Rock & Chips as in Only Fools and Horses, but he has an estranged relationship with his father Reg. It is clear that they love each other, but they are sometimes at odds, particularly regarding Reg's slacker lifestyle and when Reg verbally abuses Joan, when Del threatens to harm him if he does it again. Del is also visibly disgusted to hear that Joan is pregnant with what he incorrectly believes to be Reg's second child. By the end of the pilot episode, their relationship begins to improve somewhat, although in Only Fools and Horses it is clear that Del has still not forgiven Reg for abandoning the family after Joan's death. This is demonstrated in "Thicker than Water" when he nearly throws Reg out of the flat. But Del still appears to feel some familial loyalty to Reg, shown when he gives him some money just before his departure.
Del Boy appears to be closer to Jumbo Mills than the rest of his gang and seems to be quite promiscuous, as shown when he becomes "engaged" to several girls by presenting them with fake diamond rings.
His relationship with Frederick "Freddie the Frog" Robdal is not much elaborated on, as they share few scenes. During the series, Robdal becomes closer to the Trotters, primarily Joan, and Robdal is shown to respect Del's ability to look after himself, his hard work and his devotion to his mother. In Sleepless in Peckham, Del tells Raquel that was told to call Robdal "Uncle Fred", not knowing until years later that Robdal was Rodney's father. In the final scene, Del labels Robdal as "a professional burglar, disloyal to his friends, a womaniser, a home-breaker, a con-man, a thief, a liar, and a cheat". This is long after he has realised that Robdal is Rodney's real father, so this knowledge apparently causes him to resent Robdal greatly.
Del Boy's year of birth is contradicted in several episodes. In "Sleepless in Peckham" (2003), Rodney shows Cassandra a photo of the 1960 Jolly Boys' outing, saying that Del was 15, making his date of birth around 1945. In "Go West Young Man" (series 1, 1981), it is implied that he is 35, giving him a birth year of 1945/46. In "A Losing Streak" (series 2, 1982) and "Thicker than Water" (series 3, 1983), he claims that their father left in 1965, on his 16th birthday, making his birth year 1949. In "Tea for Three" (series 5, 1986), Rodney tells Trigger's niece Lisa that Del's 46th birthday is coming up, making the year of birth 1940, although in that scene Rodney may be lying to make Del appear older. In "The Chance of a Lunchtime" (series 7, 1991), Trigger reveals that his sister has just had her 39th birthday and is 5 years younger than himself. Trigger and Del are the same age, suggesting a birth year of 1947 or 1948. "The Class of '62" (series 7, 1991) sees Del and friends attending a class reunion, suggesting a birth year of 1946 or 1947.
The prequel drama Rock & Chips, set in 1960, shows Del Boy at 15, before Rodney has been born. This is confirmed when the teacher complains about the boys having to stay at school for another year because of a change in the law. (The school leaving age in the UK was raised to 16 in 1972.) This, however, is inconsistent with "Big Brother" (Series 1, 1981), when Del states that he is 13 years older than Rodney. If this were so, Del should have been 12 or 13 in Rock & Chips.
The 2015 novel He Who Dares... confirms that Del was born on 10 December 1945.
Del Boy works as a market trader, running his own company, Trotters Independent Traders (T.I.T.), either from out of a suitcase or from the back of his bright yellow Reliant Regal supervan. With a never-ending supply of get-rich-quick schemes and an inner belief in his ability to sell anything to anyone, he embroils "the firm", as he calls the family business, in a variety of improbable situations. This unwavering confidence had given rise to his oft-proclaimed ambition "This time next year, we'll be millionaires!" His business acumen is described in the episode "Mother Nature's Son", when Del is depressed about his financial situation and Rodney says, "The old Derek Trotter could smell a fiver in a force 9 gale. They used to say that if Del Boy fell into a Viper's Pit, he'd come up wearing snake-skin shoes."
In one of the earlier series, Del lost £2000 to a Confidence trickster.
While maintaining a tough exterior, Del still mourns the death of his mother and runs T.I.T. with Rodney. He takes great pride in having raised Rodney after their mother's premature death and has never forgiven his father for running away when Rodney was an infant. Despite their often minimal income, Del insists on caring for his elderly grandfather. When Grandad dies, his role in the family trio is taken by his younger brother Albert, who receives the same level of respect (and light-hearted abuse).
Del Boy is a petty criminal and makes no attempt to hide it unless directly confronted by the authorities. On one occasion, he claims that at least half his possessions are illegal, including the furniture. He dabbles in theft, but mostly receives stolen goods and sells them on. He pays no tax, claiming that, since he and his family do not benefit from the Welfare State, they should not have to contribute to it. An early episode implies that he is legally dead and therefore does not pay tax.
Del and Rodney become millionaires, following the sale of a priceless watch, which they discover amongst their inventory. In the feature-length episode "If They Could See Us Now", the Trotters' business is liquidated, Del Boy is declared bankrupt, and he receives a two-year suspended sentence for his years of tax evasion, with a condition that he pay off the outstanding balance within twelve months to avoid being sent to prison. Rodney becomes the Managing Director of a reformed T.I.T., but this doesn't stop Del acting as if he runs the business. He fails to make enough to pay his tax bill, but an inheritance from the recently deceased Uncle Albert gives him the money he needs.
Del Boy's autobiography called He Who Dares was released in October 2015.Only Fools and Horses (64 Episodes)
The Green Green Grass (1 Episode)
Rock & Chips (3 Episodes)
This Morning - David Jason portrayed Del Boy when introducing the competition segment of the show, saying "this time next week, you could be a quarter of a millionaire" this referencing back to one of Derek's famous quotes; "This time next year, we'll be millionaires".
Sport Relief 2014 Special - "Beckham in Peckham"
Derek "Del Boy" Trotter - He Who Dares... is a 2015 autobiography "written" by "Del Boy" Trotter released in October 2015.
The book was released in memorium of the series' creator John Sullivan. The book portrays the events of Rock and Chips and Only Fools and Horses from Del Boy's perspective. The book also covers what happened between and after the events of "Sleepless in Peckham" and "Beckham in Peckham". In marketing for the book, John Challis and Sue Holderness reprised their roles as Boycie and Marlene. It is mentioned in the book that during the events of The Green Green Grass, Del thought Boycie to be dead.