|Full name||Thomas Bertram|
|Age||17 at the beginning of the novel, 27 at the end|
|Income||The estate of Mansfield Park and its demesnes, which will be his patrimony|
|Rank||Elder son of a baronet|
|Primary residence||Mansfield Park, but he often travels and stays with friends and acquaintances|
|Parents||Sir Thomas Bertram and Lady Bertram|
|Sibling(s)||Edmund Bertram, Maria Bertram, and Julia Bertram|
Thomas Bertram is a supporting character in Jane Austen's 1814 novel, Mansfield Park. He is the elder son and heir of Sir Thomas Bertram, a baronet and wealthy landowner in Northamptonshire, who also owns an estate in Antigua.
Thomas Bertram, who is mainly called "Tom", is depicted as a person who is careless and extravagant. He is not particularly kind to his cousin Fanny Price, the poor ward of his parents who has come to live with his family. Once grown up, he is only interested in amusing himself and is careless and extravagant with money. As a result of Tom's debts, his father has to sell the living of the local parish to pay off his debts. This harms the prospects of his brother Edmund Bertram, who was intended to become a clergyman and live off the tithes of the parish. Though Tom becomes a bit ashamed of his actions, he continues to seek his pleasures.
Travel and return
Tom and his father go to Antigua to deal with problems on his estate. Tom returns before his father and finds that while he has been away, two new young wealthy people, Henry and Mary Crawford have moved to the area and are living in the parsonage with their half sister, the new clergyman's wife. Mary is romantically interested in Tom at first but he does not respond to her, and she shifts her attentions to his younger brother, Edmund. Tom leaves home again to spend some time with his friends and returns with one, Mr Yates, who is full of a thwarted project to put on an amateur production of a play somewhat risque play. Tom proposes that the party at Mansfield Park should also do this. Edmund and Fanny are opposed but the rest of the group are excited. Tom arranges for a theatre to be built in the billiard room in Mansfield Park. The play is almost ready for production when Sir Thomas returns unexpectedly early and puts a stop to the proceedings.
Tom leaves again to take part in a horse racing meet but has a fall and is injured which, combined with his drinking, causes him to become very ill. His friends abandon him and Edmund has to fetch him home to be nursed back to health. His illness causes his family to fear for his life, which is observed with interest by Mary Crawford, who wants to marry Edmund; if Tom should die, that would leave Edmund as the heir to the Bertram estates and title. Tom recovers from his illness, and develops into a more prudent man.
- Giles Ashton as the young Tom and Christopher Villiers as the grown Tom in the 1983 BBC drama serial Mansfield Park (1983 TV serial).
- Zachary Elliott-Hatton as the young Tom and James D'Arcy as the grown Tom in the 2007 ITV production aired as The Complete Jane Austen (Mansfield Park (2007 TV drama)).