Well, you can do whatever you want, but realistically during boarding is one of the worst times to ask a flight attendant anything.
Most flight attendants will not give you an upgrade to a paid class of service that gives food/drinks as would require them to account for the comped food items (or to have stocked them in the first place.)
You are more likely to convince an FA to switch to a different seat that does not offer any additional benefits (no free meals/drinks/movies) after the boarding process has ended and the door has closed.
Instead, the person you should be sweet talking into an upgrade is the gate agent, the check-in clerk or the airline lounge attendant. They are the ones who control the flight manifest, and have the power to change your seat (paid or not paid.) of those three, your best bet is with the gate agent.
Sometimes, the checkin kiosk will offer you an operational upgrade as well.
Free upgrades, however, are few and far between, but do happen. I received an upgrade from my free middle seat to a $115 paid window seat just the other day from a gate agent without my even doing anything.
Originally Posted: https://www.quora.com/Is-it-fine-if-I-ask-the-flight-attendant-if-theres-a-free-upgrade-to-comfort-or-business-class-during-boarding-the-flight
Originally Posted On: 2015-11-08