The two boroughs were united by Act of Parliament in 1571, and returned four Members
in the freeholders
Number of voters: about 300
| Date | Candidate | Votes |
|---|---|---|
| 15 Apr. 1754 | LORD JOHN CAVENDISH | |
| GEORGE BUBB DODINGTON | ||
| WELBORE ELLIS | ||
| JOHN TUCKER | ||
| 31 Dec. 1755 | Dodington And Ellis re-elected after appointment to office | |
| 28 Mar. 1761 | SIR FRANCIS DASHWOOD | |
| JOHN TUCKER | ||
| JOHN OLMIUS | ||
| RICHARD GLOVER | ||
| 9 June 1762 | DASHWOOD re-elected after appointment to office | |
| 1 Dec. 1762 | RICHARD JACKSON vice John Olmius, Baron Waltham, deceased | |
| 30 Apr. 1763 | CHARLES WALCOTT vice Dashwood, called to the Upper House | |
| 18 Mar. 1768 | DRIGUE BILLERS OLMIUS, Baron Waltham | |
| SIR CHARLES DAVERS | ||
| JEREMIAH DYSON | ||
| JOHN TUCKER | ||
| 28 Dec. 1768 | DYSON re-elected after appointment to office | |
| 14 Mar. 1774 | DYSON re-elected after appointment to office | |
| 7 Oct. 1774 | WELBORE ELLIS | |
| WILLIAM CHAFFIN GROVE | ||
| JOHN PURLING | ||
| JOHN TUCKER | ||
| 13 June 1777 | ELLIS re-elected after appointment to office | |
| 10 June 1778 | GAVRIEL STEWARD vice Tucker, vacacted his seat | |
| 7 Sept. 1780 | WELBORE ELLIS | |
| WILLIAM CHAFFIN GROVE | ||
| JOHN PURLING | ||
| WARREN LISLE | ||
| 30 Nov. 1780 | GABRIEL STEWARD vice Lisle, vacated his seat | |
| 30 Apr. 1781 | WILLIAM RICHARD RUMBOLD vice Grove, vacated his seat | |
| 18 Feb. 1782 | ELLIS re-elected after appointment to office | |
| 31 Mar. 1784 | WELBORE ELLIS | |
| JOHN PURLING | ||
| GABRIEL STEWARD | ||
| SIR THOMAS RUMBOLD | ||
| 27 Mar. 1786 | GEORGE JACKSON vice Steward, vacated his seat | |
| 27 Dec. 1788 | GABRIEL STEWARD vice Jackson, vacated his seat |
Government had considerable interest through the customs and the Crown quarries at Portland. The most important private interest belonged to the Tucker family, who for many years held the post of supervisor of the Portland quarries, and to George Bubb Dodington, who joined his interest to that of Tucker and acted as intermediary with Government. In 1744 Dodington came to an agreement with Henry Pelham by which Government should recommend to two seats in exchange for the disposal of patronage. Under this agreement, Dodington arranged the Members in 1754 with Newcastle and in 1761 with Bute.
On Dodington’s death in 1762 Tucker became sole patron, and the arrangement with Government remained unchanged. In 1779 Tucker was succeeded by his nephew Gabriel Steward, who in 1790 sold his property in the borough to William Pulteney.