Kirsty Balfour (born 21 February 1984), also known by her married name Kirsty Kettles, is a Scottish former competitive swimmer who represented Great Britain in the Olympic Games, FINA world championships and European championships, and competed for Scotland in the Commonwealth Games.

She specialized in breaststroke events.

She won a gold medal in the 200-metre breaststroke at the European Long-Course Championships in 2006, and took silver in same event at the World Championships in Melbourne in 2007.

She announced her retirement from swimming on 7 November 2008, stating she planned to do more work for her church.

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