The incident appears to have shocked and humoured nearby passengers on the flight from Luton airport to the Spanish party island on Friday, according to a video posted to social media site X, formerly known as Twitter.
A crew member can be seen opening the door on the young couple in front of a number of passengers in the rear of the plane, who were clapping and cheering him on to catch them in the act.
A partially clothed man in the small toilet quickly pulled the door back shut as there were shouts and laughs of disbelief from other passengers.
Nearby people put their hands over their faces in shock and asked if their friends had captured the moment on camera.
The crew member who exposed the couple did not appear to know how to respond. He stood near the closed door and spoke with another crew member before the video ended.
An easyJet spokesperson confirmed that the flight on Friday September 8 was met by police when it arrived in Ibiza “due to the behaviour of two passengers onboard”.
It is unclear if any arrests took place in Ibiza.
It is illegal to intentionally engage in sexual activities in a public lavatory, under Section 71 of the Sexual Offences Act.
The incident comes just days after a Delta Airlines flight bound for Spain was diverted because a passenger suffered diarrhoea “all through the plane”, according to reports.
The plane left Atlanta city in the state of Georgia on September 1 but had to divert back to Atlanta just hours later after the bizarre “biohazard issue”.
On September 4 a Wizz Air flight from Tel Aviv to London Luton airport was forced to land in Belgrade after the “erratic” behaviour of one passenger, The Sun reported.
Victor Troboloni, 45, told the newspaper he tackled the man after he tried to force open the emergency door and went to punch a male flight attendant, placing him in a headlock before crew members also helped to hold him down.