Labour had held its seat in the Delapre and Briar Hill ward after a by-election was held yesterday (November 29).
The vote was sparked by the resignation of Labour councillor Vicky Culbard due to ill health, and the party retained its seat, with candidate Emma Roberts elected to Northampton Borough Council in her place.
Coming out on top with 914 votes, Ms Roberts comfortably saw off the challenge of Conservative candidate Daniel Soan, who polled 549 votes, and independent candidate Nicola McKenna, who came in third place with 417 votes.
Michael Maher (Liberal Democrats) and Denise Donaldson (Green Party) came fourth and fifth respectively with 133 and 95 votes.
Just 2,113 residents out of an electorate of 10,516 voted in the by-election, a turnout of 20.9 per cent. There were five rejected ballot papers.
Emma Roberts becomes the third councillor for the Delapre and Briar Hill ward, alongside Conservative councillor Graham Walker and independent councillor Julie Davenport.