Bampfield was the eldest son and heir of Sir Amias Bampfield (c. 1560 – c. 1626), MP, of Poltimore and North Molton, by his wife Elizabeth Clifton, who was a daughter of Sir John Clifton of Barrington Court, Somerset.
Bampfield matriculated at Exeter College, Oxford on 13 July 1604, aged 18.
In 1621 he was elected a Member of Parliament for Tiverton, Devon.
He was elected an MP for Devon in 1628 and sat until 1629, when King Charles I decided to rule without parliament for eleven years.
[2] In 1631 he founded almshouses in memory of his late wife.