James posted the sweet pic alongside the simple emoji caption: '❤️'.
The duo have been dating since last October, according to Confidential, when they stepped out together while on holiday in Byron Bay.
They also headed to Melbourne together last week to celebrate Home and Away's 30th anniversary.
'On screen and off screen we are ... well I am, really enjoying getting to know each other,' James told The Herald Sun.
'And we are very special to each other,' James said.
Sarah added: 'I did not even have to create any chemistry when I was on screen with Jimmy, it was all just there, it was not a job.'
The Packed to the Rafters co-stars are parents to daughter Scout, 5.