Passengers stunned as Madonna sits alongside them on budget flight from London

Madonna is often referred to as the Queen of Pop, with tens of millions of fans across the world.

The Material Girl singer is one of the best-selling female artists of all time, complete with bank balance to match.

The performer is estimated to be worth $800 million – making her one of the richest singers on the planet.

So it came as quite the shock to passengers when she rocked up on a budget Halloween flight from London to Lisbon.

The 59-year-old was spotted clutching her phone in the window seat of an Air Portugal flight to the country’s capital.

A fellow passenger was so shocked by the sight of Madonna aboard the scheduled public flight that they snapped the moment and posted it online.

They captioned the image: “If you fly with M! London – Lisbon. 2017.10.31.” according to the Evening Standard.

It’s not known if she travelled with carry on bags, or checked in larger luggage at additional cost.

Madonna did allow herself some extras aboard the budget airline, however, pitching for one of the more spacious seats at the front of the aircraft.

And her family probably appreciated the flight as she dashed between visiting two of her sons.

It’s believed she had been visiting son Rocco Ritchie, whose father is Guy Ritchie, in London before jetting off to see her other son, David Banda, in Portugal.

Fans struggled to believe the sight of Madonna on board with one tweeting: “Can you imagine boarding a plane and then sitting next to the f****** QUEEN?! I JUST CAN’T. @Madonna (sic).”

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Another posted: “If I got on a plane and MADONNA was sitting next to me in coach I would LOSE MY MIND.”

A third was shocked the star doesn’t have her own plane, writing: “Wtf madonna doesnt have her own plane? Xd.”

The singer is thought to be living between the UK, US and Portugal after son David joined a football training camp in the European country.

The 12-year-old, who Madonna adopted from Malawi in 2006, recently signed to the Benfica football team youth academy.