Thomas was the eldest son of the famous writer, Geoffrey Chaucer, by his wife Philippa the daughter of Sir Payne Roet and sister of Catherine Swnyford, mistress and afterwards wife of Prince John of Gaunt, the Duke of Lancaster. Early in life, he married Matilda the second daughter and co-heiress of John Burghersh, Lord Kerdeston, the nephew of Henry Burghersh, Bishop of Lincoln, Treasurer and Chancellor of the Kingdom. His marriage brought him large estates, central to which was the manor of Ewelme in Oxfordshire.

It is evident that Thomas' connection with the Duke of Lancaster was profitable to him. He was appointed Chief Butler to King Richard II and, on 20th March 1399, received a pension of twenty marks (£13-6s-8d) a year in exchange for certain offices granted him by the Duke, paying at the same time five marks (£3-6s-8d) for the confirmation of two annuities of £10, charged on the Duchy of Lancaster and also granted by the Duke. These annuities were confirmed to him by Henry IV, who also appointed Thomas, Constable of Wallingford Castle and Steward of the Honours of Wallingford and St. Valery (based at Hinton Waldrist) and of the Chiltern Hundreds, with £40 a year as a stipend and £10 for a deputy. For a man dividing his time between Ewelme and Wallingford, it was only naturally that in 1400 & 1402, he was appointed Sheriff of Berkshire and Oxfordshire.

About the same time, Thomas succeeded his father as Forester of North Petherton Park (Somerset). On 5th November 1402, he received a grant of Chief Butlership for life. On 23rd February 1411, the Queen gave him the manor of Woodstock (Oxon) and other estates during her life and, on 15th March, the King assigned them to him after her death.

Thomas sat as Member of Parliament for Oxfordshire fourteen times between 1400 and 1431. He was chosen as Speaker of the House of Commons in the Parliament that met at Gloucester in 1407 and, on 9th November, reminded the King that the accounts of the expenditure of the last subsidy had not been rendered. The Chancellor interrupted him, declaring that they were not ready and that, for the future, the Lords would not promise them. He was chosen, again, in 1410 and in 1411, when, on making his 'protestation' and claiming the usual permission of free speech, he was answered by the King that he might speak as other speakers had done, but that no novelties would be allowed. He asked for a day's grace and then made an apology. He was again chosen in 1414. In that year he also received a Commission in which he is called 'domicellus,' to treat about the marriage of King Henry V, and to take the homage of the Duke of Burgundy. The next year, Thomas served with the King in France, bringing to the field of battle twelve men-at-arms and thirty-seven archers, and was present at the Battle of Agincourt. In 1417, he was employed to arrange a peace with the French. On the accession of King Henry VI, he appears to have been superseded in the Chief Butlership, but to have regained it shortly afterwards. In January 1424, he was appointed a member of the council with a salary of £40 and, the next year, was one of the commissioners appointed to investigate a dispute between the Earl Marshal and the Earl of Warwick over precedence. In 1431, he was appointed one of the executors of the will of the Duchess of York.

Thomas was a member of the Fraternity of the Holy Cross in Abingdon and, shortly before his death, he is said to have designed the town's famous Market Cross that was eventually erected in 1438. However, Thomas did not live to see it. He died on 18th Nocember 1434 and was buried at Ewelme, where his widow, who died two years later, was also buried with him. They have a fine brass memorial in the parish church. He was a very wealthy man, for, in the list drawn up after his death in 1436, of those from whom the council proposed to borrow money for the war with France, he was put down for £200, the largest sum asked from any on the list except four. He left only one child, Alice, who married, first at the age of only eleven, Sir John Philip. Her father purchased Donnington Castle for the couple, but Sir John died later the same year and it is unlikely that they ever took up residence. Alice married, secondly, Thomas Montacute, 4th Earl of Salisbury (d.1428). She had no children by either husband. Thirdly, she was united with William de la Pole, Earl and, afterwards, Duke of Suffolk (beheaded 1450), by whom she had two sons and a daughter. Her magnificent tomb may also be seen at Ewelme.