The 1900 Portsmouth by-election was a parliamentary by-election held on 3 May 1900 for one of the two seats in the British House of Commons constituency of Portsmouth in Hampshire.

Vacancy

The seat had become vacant when the Liberal Member of Parliament (MP) Walter Clough had resigned his seat on 23 April 1900 by the technical device of accepting appointment as Steward of the Manor of Northstead, a notional "office of profit under The Crown". The writ for the by-election was moved in the Commons three days later, on 26 April.

Previous result

Candidates

The Liberal Party selected Thomas Bramsdon, a 43-year-old solicitor and a native of Portsmouth. The Conservative Party selected 29-year-old James Majendie.

Result

The result was a narrow victory for Bramsdon. However, he held the seat only briefly; at the general election in October 1900, he lost his seat to Majendie.