Mildred Cox thought she’d upgraded her seat from economy class to business class with a $594 bid. But ITA kept her in economy class anyway — and then it decided to keep her $594. Can an airline do ...

Premium economy often costs around 50% more than economy, although this varies widely and varies by sub-class.

Experts weigh in on the pros and cons of spending a bit more for a cabin class that bridges the gap between business and economy.