If you want to sit in First Class, you need a first class ticket. You might be able to score an upgrade, but you pay for that also. If you try to sit there without a First Class ticket, you will be embarrassingly removed.

Absolutely not. In 2026, trying to "self-upgrade" by sitting in an empty First Class or Business Class seat is considered a serious violation of airline policy and can lead to being offloaded or banned from the carrier. Airline manifests are digitally synced in real-time; the cabin crew knows exactly which seats are paid for and which should be vacant. These premium seats represent a specific revenue tier that includes higher-quality food, alcohol, and labor-intensive service. If you move without permission, you are essentially "stealing" a service you didn't pay for. In 2026, some airlines have even implemented weight-and-balance sensors in seats that alert the crew via their tablets if an unassigned seat becomes occupied. If you see an empty seat you want, the only proper way to obtain it is to ask the flight attendant if a paid "on-board upgrade" is available, which they can often process via a mobile card reader.