The couple and their children, Teddy, seven, Charlton, five, Coco, 23 months, and Beau, six months, first moved to Geneva last year (20) amid the COVID-19 pandemic and they have reportedly now decided to make it their permanent base.
A source told Britain's The Sun newspaper, "Robbie and his family are delighted. They love the pace of life here. They love the open space and the lake nearby. The area is used to wealthy inhabitants and their privacy is totally respected."
Robbie, 46, reportedly struck a deal to buy the lavish family home over a round of golf with businessman Nicolas Brunschwig.
The insider explained, "The Golf Club De Geneve is very exclusive. You have to know the right people to even get a look-in and that's before even paying the massive fees."
"Robbie is a first-class golfer and loves it there. He met Brunschwig and they did the deal."
Last year, the "Angels" singer revealed he and Ayda, 41, had moved to Switzerland with their family as he was worried about catching COVID-19.
When asked in an interview if he was living in his Los Angeles or Malibu home amid the pandemic, he said, "No I'm not. I'm somewhere in Switzerland up a mountain."
"Well, I'm a bit neurotic and I thought where can I place myself where it won't get me? And I thought, well I'll just live up the Mont Blanc for six months… it's really warm actually, it's really lovely."
However, Robbie recently had to quarantine at a villa in St. Barts with his family after contracting coronavirus.