The couple, who have been dating since October according to Confidential, went public with their romance whilst looking 'loved up' in new photos from their holiday in Byron Bay.
In the images the pair can be seen holding hands and cuddling up to each other.
Roberts joined the Channel 7 drama in 2017 and plays Willow Harris.
This isn't the first time Stewart has been linked to one of his co-stars.
The 42-year-old was dated fellow Summer Bay resident Isabella Giovinazzo in 2016.
Stewart was previously engaged to actress Jessica Marais. The Packed to the Rafters co-stars are parents to daughter Scout, 5.
