A Gold Coast couple have revealed the moment Ben Roberts‑Smith unexpectedly turned up on their doorstep on Anzac Day to thank them for a public show of support.

Accused war criminal Ben Roberts‑Smith was at the Currumbin RSL dawn service with his partner and family on the Gold Coast last Saturday when he spotted an Australian flag and a giant banner flying from a top‑floor balcony in the distance that read 'We support BRS'.

Australia's most decorated soldier spent 10 days in Sydney's Silverwater Jail after he was arrested on April 7 and charged with murdering or ordering the murders of five unarmed detainees while deployed in Afghanistan between 2009 and 2012.

Touched by the pledge of support, Roberts‑Smith went out of his way after the service to drop by the home to personally thank strangers Geoff and Lee.

The couple were stunned to find the Victoria Cross recipient at their door.

'Holy s*** that's Ben Roberts‑Smith!' Geoff said to his wife, Lee.

The couple had put up the banner last Saturday, knowing that dawn service attendees would see it from the surf club below.

But they had no idea that Roberts‑Smith would be among the large crowd, just a week after he was released from custody.

Roberts-Smith happily posed for a photo with the couple and wished them the best during the emotional encounter.

'Ben has had a rough time so we just wanted to show him support,' Geoff told news.com.au.

'We were just in complete shock. He brought his partner, his parents waited in the car, and he introduced us to his family. It was a very kind gesture from him.'

Roberts-Smith was inundated with support at the dawn service, where thousands braved the rain.

Photos showed a beaming Roberts-Smith chatting with veterans and current servicemen and women, shaking hands, and posing for selfies with dozens of supporters of all ages.

One man told him to 'keep fighting, mate', prompting the former SAS soldier to reply that the support was 'overwhelming'. 

'I've never thought about not coming, I was always going to be here,' Roberts-Smith told the ABC.

He is due to reappear in court on June 4.

Each of the charges against Roberts-Smith carries a maximum penalty of life in prison. He has always denied involvement in any unlawful killings.

He is yet to enter a plea, but has persistently denied the allegations against him.