Billie Eilish poses for a photograph.

Singer Billie Eilish was spotted flying in economy on a commercial airline a few days ahead of her show at Reading and Leeds Festivals in the UK.

The 21-year-old singer could be seen sitting on one of the passenger seats in an economy class of a commercial airline in a video uploaded via TikTok, reports aceshowbiz.com.

In the clip that soon went viral, she appeared comfortable despite not flying in a private jet. The footage went on to show Billie getting out of the airplane in an oversized blue hoodie and a gray hat that came with blue star patterns on it.

She was also documented carrying a black backpack on her shoulder. At that time, she was standing while being surrounded by a number of people who appeared to be her team.

The clip additionally displayed a screenshot of Billie's selfie which she uploaded on her Instagram Story around the same time of the flight. In the snap, she could be seen wearing the same hoodie and beanie that were documented in the beginning of the fan's video.

The fan who released the video claimed that other passengers of the flight were not allowed to use a bathroom in the front and only one in the back which could be used at that time. The fan also shared that they tried to get closer to Billie during the flight.

However, her team allegedly prohibited them from approaching the 'Ocean Eyes' singer. In the comments section of the footage, one fan could not help but gush, "Omg shes so humble being in economy!!" adding a crying face emoji.

Meanwhile, another suggested, "I would just go to the bathroom in the front every 5 minutes to look at her." In the meantime, a third said: "Guys, she doesn't fly that much on private jets bc she's actually doing something for our environment lmao." Similarly, a fourth stated, "I actually love that she has the money for a private jet but doesn't do that because of her campaign for protecting the environment."

Indo-Asian News Service