[2] Powlett was home in time to stand successfully as Whig at a by-election for Lymington on 7 December 1705.

He was created Lord Powlett of Basing on 12 April 1717 and had to give up his seat in the House of Commons.

In 1722 he succeeded to his father's estates and to the Dukedom of Bolton, making him one of the largest landowners in Hampshire and bringing control of some parliamentary seats; thus he became one of the principal electoral managers for the Whig government.

He was appointed High Steward of Winchester, Warden of the New Forest and Lord Lieutenant of Hampshire and Dorset in the same year.

A notice of 1729 records that “The Jockey Club, consisting of several Noblemen and Gentlemen, are to meet one Day next Week at Hackwood, the Duke of Bolton’s Seat in Hampshire, to consider of the Methods for the better keeping of their respective Strings of Horses at New Market.”[4] In 1733 another newspaper noted he was going "to dine with the Jockey Club, at William's Coffee-house, St.

The third Duke of Bolton died in 1754, aged 68, at Royal Tunbridge Wells and was buried at Basing.