The 1869 Radnor Boroughs by-election was fought on 25 February 1869. The by-election was fought due to the resignation of the incumbent MP of the Liberal Party, Richard Green-Price. It was won by the Liberal candidate, Spencer Cavendish who was the Marquess of Hartington.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! colspan="3" style="text-align:right;" scope=row | Registered electors
References.
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