Conservative Charlotte Howard has been elected a St Edmundsbury Borough councillor for the Abbeygate ward, in Bury St Edmunds.
The by-election followed the resignation of Richard Rout.
Mrs Howard, an optical receptionist, has lived and worked in Bury St Edmunds for more than 40 years.
She said: “I feel fantastic and thrilled to bits to get in. The other candidates did well so I want to congratulate all of them.”
Her win was announced ahead of the Suffolk County Council election count at Bury Leisure Centre.
The voter turnout was 33.75 per cent with 1,275 votes cast out of a 3,778 strong electorate - with 11 ballot papers rejected.