Branson's Makepeace Island on the Sunshine Coast was opened to residents whose homes had been destroyed or damaged by fires at Noosa North Shore, the ABC reports.
Mike Hancock was among the 10 residents whose homes were lost in fires which started on Friday.
All 10 were invited to stay on the island, which is the Australian home of the entrepreneurial Englishman.
Mr Hancock told the ABC the offer and generosity was overwhelming.
"In the middle of the fire [Makepeace manager] Jason Styles came over and said we could come stay at the island," he said.
Firemen hose down the remains of three houses that have been destroyed by fire on the Noosa North Shore on the Sunshine Coast, Saturday, August 19, 2017. Source: AAP
The offer came from Mr Styles via Virgin Australia co-founder Brett Godfrey, who owns the island with Sir Richard.
North Shore home owner David Wright is staying on the island with wife Kym and their 29-year-old autistic son Brody.
He told the ABC that sleeping in Sir Richard's bed "feels pretty much the same as my bed".
Sir Richard purchased the island in 2001 as his Australian home away from home.
The island was used exclusively as a getaway for Virgin staff and guests until he opened it to the public in 2011 as a private resort, which now attracts a hefty price tag of $5500 a night for four people.
A Makepeace spokeswoman declined the ABC's requests to comment, saying neither Sir Richard or Mr Godfrey were looking for publicity out of their offer.