Heledd trained at the Royal Welsh College of Music and Drama.

Theatre includes Henry V (Shakespeare at the Tobacco Factory); Ice Road (Raucous); The Lightning Path (Small World); Windsong's of the Blessed Bay (Theatr Cadair); TI.ME. (Cwmni Pluen & Sherman Cymru); Y Fenyw Ddaeth O’r Mor (Theatr Genedlaethol Cymru); A Child’s Christmas in Wales (Wales Theatre Company); Land of the Dragon (Puppet Soup at the Edinburgh Fringe); In Light of Tom Mathias – Incubator Project (Wales Millennium Centre); Rhwng Dau Fyd (Living Pictures & Sherman Cymru); Say It With Flowers (Sherman Theatre).

Television includes Holby City, Ordinary Lies, Enid a Lucy, 35 Diwrnod, Amser Maith Yn Ol, Gwaith/Cartef.

Heledd was awarded the Laurence Olivier Bursary Award in 2012.