The artist was born in Luton, Bedfordshire and studied there at the School of Art, then at Loughborough College of Art & Design, followed by postgraduate studies at the RA Schools and a Junior Fellowship at Cardiff College. Since 1979 she has been a part-time lecturer at Falmouth College of Art.

In 1995 Mabbutt won the John Moores Liverpool Art Prize. She exhibits regularly at the Paton Gallery, London, and participates in many group shows in Cornwall and beyond. Her work has been shown at the Metropolitan Museum of Art in New York and is held in corporate collections.