The 1890 Partick by-election was a parliamentary by-election held in Scotland on 11 February 1890 for the British House of Commons constituency of Partick. It was caused by the death of the constituency's sitting Liberal Unionist Member of Parliament (MP) Alexander Craig Sellar, who had held the seat since the 1885 general election. He had been elected as a Liberal in 1885, but joined the breakaway Liberal Unionists in 1886, and was re-elected at the election of 1886 as a Liberal Unionist.