 As head of the family, Pitt inherited both his grandfather's immense fortune and his parliamentary boroughs - he had the complete power to nominate both MPs at Old Sarum and one of the two at Okehampton, as well as considerable influence in at least two Cornish boroughs, Camelford and Grampound.He had himself elected Member of Parliament for Okehampton in 1727, the first election after he came of age, and represented the borough until 1754; but on a number of occasions he was also elected for Old Sarum, which meant that when he chose to sit for Okehampton the Old Sarum seat was free to offer at a by-election to somebody else who had failed to get into Parliament.Pitt was Assay master of the Stannaries from March 1738 to February 1742 and Lord Warden of the Stannaries from February 1742 to March 1751, when the Cornish Stannary Parliament met for the last time.