The Duke and Duchess of Sussex have officially said goodbye to Frogmore Cottage, which was gifted to them by the late Queen Elizabeth II.

But it’s not just the keys that have been handed over.

Along with their departure from the Windsor residence came the hefty loss of millions of pounds.

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Frogmore was originally intended as a long-term base for the couple, but just months after completing major renovations in 2019, initially funded in part by a Sovereign Grant and later fully reimbursed by the Sussexes, they stepped back from royal duties and relocated to California.

The couple now reside in Montecito with their two children, Prince Archie and Princess Lilibet.

Terry Fisher of ‘We Buy Any Home’ explained why their investment was ultimately ‘futile’.

“Even if someone makes improvements or invests in a royal property, that doesn’t give them a lasting stake in it,” he told Hello.

Mr Fisher continued: “It is more like an extended loan, and when that time ends, it is returned to the Crown.”

According to reports, Prince Harry and Meghan received no reimbursement for the personal funds spent modernising the Grade-II listed home. That includes everything from an eco-friendly boiler system delivering low-carbon heat and endless hot water to top-tier security features, now lost to the Crown Estate.

“The rules around royal homes are very different to those in everyday property ownership,” Mr Fisher added.

“When it comes to legal rights, there simply are none in the way most homeowners understand them.”

The couple had previously reimbursed £2.4 million (over $A4.9 million) in public funds used for the initial renovations after facing public criticism.

Now, the final chapter in their UK housing saga closes with Frogmore back under Crown control.

Their departure from the cottage marks more than just a change of address, and it is a symbolic severing of one of the last ties to royal life in Britain.

It’s yet another signal that Prince Harry and Meghan have no plans to return to royal roles, instead continuing to build their future in a different country.